diff --git a/src/main/java/cc/ryanc/halo/model/entity/PostCategory.java b/src/main/java/cc/ryanc/halo/model/entity/PostCategory.java
index 967c46d2c..a38e7b656 100644
--- a/src/main/java/cc/ryanc/halo/model/entity/PostCategory.java
+++ b/src/main/java/cc/ryanc/halo/model/entity/PostCategory.java
@@ -21,7 +21,7 @@ import java.util.Objects;
 @SQLDelete(sql = "update post_categories set deleted = true where id = ?")
 @Where(clause = "deleted = false")
 @Data
-@ToString
+@ToString(callSuper = true)
 public class PostCategory extends BaseEntity {
 
     @Id
diff --git a/src/main/java/cc/ryanc/halo/model/entity/PostTag.java b/src/main/java/cc/ryanc/halo/model/entity/PostTag.java
index 7473b1e5e..7a0a3e556 100644
--- a/src/main/java/cc/ryanc/halo/model/entity/PostTag.java
+++ b/src/main/java/cc/ryanc/halo/model/entity/PostTag.java
@@ -19,7 +19,7 @@ import java.util.Objects;
 @Table(name = "post_tags")
 @SQLDelete(sql = "update post_tags set deleted = true where id = ?")
 @Where(clause = "deleted = false")
-@ToString
+@ToString(callSuper = true)
 public class PostTag extends BaseEntity {
 
     @Id
diff --git a/src/main/java/cc/ryanc/halo/model/projection/CommentCountProjection.java b/src/main/java/cc/ryanc/halo/model/projection/CommentCountProjection.java
new file mode 100644
index 000000000..dcbd0aa30
--- /dev/null
+++ b/src/main/java/cc/ryanc/halo/model/projection/CommentCountProjection.java
@@ -0,0 +1,21 @@
+package cc.ryanc.halo.model.projection;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+/**
+ * Comment count projection
+ *
+ * @author johnniang
+ * @date 3/22/19
+ */
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class CommentCountProjection {
+
+    private Long count;
+
+    private Integer postId;
+}
diff --git a/src/main/java/cc/ryanc/halo/repository/PostCategoryRepository.java b/src/main/java/cc/ryanc/halo/repository/PostCategoryRepository.java
index 9ed98f8e2..e70e8f6ac 100644
--- a/src/main/java/cc/ryanc/halo/repository/PostCategoryRepository.java
+++ b/src/main/java/cc/ryanc/halo/repository/PostCategoryRepository.java
@@ -62,4 +62,22 @@ public interface PostCategoryRepository extends BaseRepository<PostCategory, Int
      */
     @NonNull
     List<PostCategory> findAllByCategoryId(@NonNull Integer categoryId);
+
+    /**
+     * Deletes post categories by post id.
+     *
+     * @param postId post id must not be null
+     * @return a list of post category deleted
+     */
+    @NonNull
+    List<PostCategory> deleteByPostId(@NonNull Integer postId);
+
+    /**
+     * Deletes post categories by category id.
+     *
+     * @param categoryId category id must not be null
+     * @return a list of post category deleted
+     */
+    @NonNull
+    List<PostCategory> deleteByCategoryId(@NonNull Integer categoryId);
 }
diff --git a/src/main/java/cc/ryanc/halo/repository/PostTagRepository.java b/src/main/java/cc/ryanc/halo/repository/PostTagRepository.java
index f4abc2a76..8323f28db 100644
--- a/src/main/java/cc/ryanc/halo/repository/PostTagRepository.java
+++ b/src/main/java/cc/ryanc/halo/repository/PostTagRepository.java
@@ -63,4 +63,21 @@ public interface PostTagRepository extends BaseRepository<PostTag, Integer> {
     @NonNull
     List<PostTag> findAllByPostIdIn(@NonNull Iterable<Integer> postIds);
 
+    /**
+     * Deletes post tags by post id.
+     *
+     * @param postId post id must not be null
+     * @return a list of post tag deleted
+     */
+    @NonNull
+    List<PostTag> deleteByPostId(@NonNull Integer postId);
+
+    /**
+     * Deletes post tags by tag id.
+     *
+     * @param tagId tag id must not be null
+     * @return a list of post tag deleted
+     */
+    @NonNull
+    List<PostTag> deleteByTagId(@NonNull Integer tagId);
 }
diff --git a/src/main/java/cc/ryanc/halo/service/CommentService.java b/src/main/java/cc/ryanc/halo/service/CommentService.java
index 1036131fb..94f22cc40 100644
--- a/src/main/java/cc/ryanc/halo/service/CommentService.java
+++ b/src/main/java/cc/ryanc/halo/service/CommentService.java
@@ -7,6 +7,11 @@ import cc.ryanc.halo.service.base.CrudService;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
 
 /**
  * Comment service.
@@ -33,4 +38,22 @@ public interface CommentService extends CrudService<Comment, Long> {
      */
     @NonNull
     Page<CommentVO> pageBy(@NonNull CommentStatus status, @NonNull Pageable pageable);
+
+    /**
+     * Lists comments by post id.
+     *
+     * @param postId post id must not be null
+     * @return a list of comment
+     */
+    @NonNull
+    List<Comment> listBy(@NonNull Integer postId);
+
+    /**
+     * Count by post id collection.
+     *
+     * @param postIds post id collection
+     * @return a count map, key: post id, value: comment count
+     */
+    @NonNull
+    Map<Integer, Long> countByPostIds(@Nullable Collection<Integer> postIds);
 }
diff --git a/src/main/java/cc/ryanc/halo/service/PostCategoryService.java b/src/main/java/cc/ryanc/halo/service/PostCategoryService.java
index 58ad8d541..ee37d4e8d 100644
--- a/src/main/java/cc/ryanc/halo/service/PostCategoryService.java
+++ b/src/main/java/cc/ryanc/halo/service/PostCategoryService.java
@@ -5,6 +5,7 @@ import cc.ryanc.halo.model.entity.Post;
 import cc.ryanc.halo.model.entity.PostCategory;
 import cc.ryanc.halo.service.base.CrudService;
 import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
 
 import java.util.Collection;
 import java.util.List;
@@ -35,7 +36,7 @@ public interface PostCategoryService extends CrudService<PostCategory, Integer>
      * @return a category list map (key: postId, value: a list of category)
      */
     @NonNull
-    Map<Integer, List<Category>> listCategoryListMap(Collection<Integer> postIds);
+    Map<Integer, List<Category>> listCategoryListMap(@Nullable Collection<Integer> postIds);
 
     /**
      * Lists post by category id.
@@ -54,7 +55,7 @@ public interface PostCategoryService extends CrudService<PostCategory, Integer>
      * @return a list of post category
      */
     @NonNull
-    List<PostCategory> mergeOrCreateByIfAbsent(@NonNull Integer postId, Set<Integer> categoryIds);
+    List<PostCategory> mergeOrCreateByIfAbsent(@NonNull Integer postId, @Nullable Set<Integer> categoryIds);
 
     /**
      * Lists by post id.
@@ -82,4 +83,22 @@ public interface PostCategoryService extends CrudService<PostCategory, Integer>
      */
     @NonNull
     Set<Integer> listCategoryIdsByPostId(@NonNull Integer postId);
+
+    /**
+     * Removes post categories by post id.
+     *
+     * @param postId post id must not be null
+     * @return a list of post category deleted
+     */
+    @NonNull
+    List<PostCategory> removeByPostId(@NonNull Integer postId);
+
+    /**
+     * Removes post categories by category id.
+     *
+     * @param categoryId category id must not be null
+     * @return a list of post category deleted
+     */
+    @NonNull
+    List<PostCategory> removeByCategoryId(@NonNull Integer categoryId);
 }
diff --git a/src/main/java/cc/ryanc/halo/service/PostService.java b/src/main/java/cc/ryanc/halo/service/PostService.java
index 798f41422..178c3bfae 100755
--- a/src/main/java/cc/ryanc/halo/service/PostService.java
+++ b/src/main/java/cc/ryanc/halo/service/PostService.java
@@ -2,9 +2,7 @@ package cc.ryanc.halo.service;
 
 import cc.ryanc.halo.model.dto.post.PostMinimalOutputDTO;
 import cc.ryanc.halo.model.dto.post.PostSimpleOutputDTO;
-import cc.ryanc.halo.model.entity.Category;
 import cc.ryanc.halo.model.entity.Post;
-import cc.ryanc.halo.model.entity.Tag;
 import cc.ryanc.halo.model.enums.PostStatus;
 import cc.ryanc.halo.model.enums.PostType;
 import cc.ryanc.halo.model.vo.PostDetailVO;
@@ -15,7 +13,6 @@ import org.springframework.data.domain.Pageable;
 import org.springframework.lang.NonNull;
 import org.springframework.transaction.annotation.Transactional;
 
-import java.util.List;
 import java.util.Set;
 
 /**
@@ -26,23 +23,6 @@ import java.util.Set;
  */
 public interface PostService extends CrudService<Post, Integer> {
 
-    /**
-     * Save post with tags and categories
-     *
-     * @param post       post
-     * @param tags       tags
-     * @param categories categories
-     * @return saved post
-     */
-    Post save(Post post, List<Tag> tags, List<Category> categories);
-
-    /**
-     * Remove post and relationship
-     *
-     * @param id id
-     */
-    void remove(Integer id);
-
     /**
      * Lists latest posts of minimal.
      *
diff --git a/src/main/java/cc/ryanc/halo/service/PostTagService.java b/src/main/java/cc/ryanc/halo/service/PostTagService.java
index 75bf25e3a..d47a72cfd 100644
--- a/src/main/java/cc/ryanc/halo/service/PostTagService.java
+++ b/src/main/java/cc/ryanc/halo/service/PostTagService.java
@@ -7,6 +7,7 @@ import cc.ryanc.halo.model.entity.Tag;
 import cc.ryanc.halo.service.base.CrudService;
 import org.springframework.data.domain.Sort;
 import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
 
 import java.util.Collection;
 import java.util.List;
@@ -46,7 +47,7 @@ public interface PostTagService extends CrudService<PostTag, Integer> {
      * @return tag map (key: postId, value: a list of tags)
      */
     @NonNull
-    Map<Integer, List<Tag>> listTagListMapBy(Collection<Integer> postIds);
+    Map<Integer, List<Tag>> listTagListMapBy(@Nullable Collection<Integer> postIds);
 
     /**
      * Lists posts by tag id.
@@ -65,7 +66,7 @@ public interface PostTagService extends CrudService<PostTag, Integer> {
      * @return a list of post tag
      */
     @NonNull
-    List<PostTag> mergeOrCreateByIfAbsent(@NonNull Integer postId, Set<Integer> tagIds);
+    List<PostTag> mergeOrCreateByIfAbsent(@NonNull Integer postId, @Nullable Set<Integer> tagIds);
 
     /**
      * Lists post tags by post id.
@@ -93,4 +94,22 @@ public interface PostTagService extends CrudService<PostTag, Integer> {
      */
     @NonNull
     Set<Integer> listTagIdsByPostId(@NonNull Integer postId);
+
+    /**
+     * Removes post tags by post id.
+     *
+     * @param postId post id must not be null
+     * @return a list of post tag
+     */
+    @NonNull
+    List<PostTag> removeByPostId(@NonNull Integer postId);
+
+    /**
+     * Removes post tags by tag id.
+     *
+     * @param tagId tag id must not be null
+     * @return a list of post tag
+     */
+    @NonNull
+    List<PostTag> removeByTagId(@NonNull Integer tagId);
 }
diff --git a/src/main/java/cc/ryanc/halo/service/impl/PostCategoryServiceImpl.java b/src/main/java/cc/ryanc/halo/service/impl/PostCategoryServiceImpl.java
index 1ff9f9a68..b8b51a911 100644
--- a/src/main/java/cc/ryanc/halo/service/impl/PostCategoryServiceImpl.java
+++ b/src/main/java/cc/ryanc/halo/service/impl/PostCategoryServiceImpl.java
@@ -154,4 +154,18 @@ public class PostCategoryServiceImpl extends AbstractCrudService<PostCategory, I
 
         return postCategoryRepository.findAllCategoryIdsByPostId(postId);
     }
+
+    @Override
+    public List<PostCategory> removeByPostId(Integer postId) {
+        Assert.notNull(postId, "Post id must not be null");
+
+        return postCategoryRepository.deleteByPostId(postId);
+    }
+
+    @Override
+    public List<PostCategory> removeByCategoryId(Integer categoryId) {
+        Assert.notNull(categoryId, "Category id must not be null");
+
+        return postCategoryRepository.deleteByCategoryId(categoryId);
+    }
 }
diff --git a/src/main/java/cc/ryanc/halo/service/impl/PostServiceImpl.java b/src/main/java/cc/ryanc/halo/service/impl/PostServiceImpl.java
index 72218bc73..6324160fe 100644
--- a/src/main/java/cc/ryanc/halo/service/impl/PostServiceImpl.java
+++ b/src/main/java/cc/ryanc/halo/service/impl/PostServiceImpl.java
@@ -23,7 +23,9 @@ import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Sort;
 import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.util.Assert;
 
 import java.util.Collections;
@@ -54,6 +56,8 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
 
     private final PostCategoryService postCategoryService;
 
+    private final CommentService commentService;
+
     public PostServiceImpl(PostRepository postRepository,
                            TagService tagService,
                            CategoryService categoryService,
@@ -160,7 +164,7 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
     }
 
     /**
-     * Count posts by status and type
+     * Counts posts by status and type
      *
      * @param status status
      * @param type   type
@@ -191,8 +195,10 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
         // Check url
         long count;
         if (post.getId() != null) {
+            // For updating
             count = postRepository.countByIdNotAndUrl(post.getId(), post.getUrl());
         } else {
+            // For creating
             count = postRepository.countByUrl(post.getUrl());
         }
 
@@ -229,7 +235,7 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
     }
 
     /**
-     * Get post by url.
+     * Gets post by url.
      *
      * @param url  post url.
      * @param type post type enum.
@@ -250,8 +256,28 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
         return convertTo(post);
     }
 
+    @Override
+    @Transactional
+    public Post removeById(Integer postId) {
+        Assert.notNull(postId, "Post id must not be null");
+
+        log.debug("Removing post: [{}]", postId);
+
+        // Remove post tags
+        List<PostTag> postTags = postTagService.removeByPostId(postId);
+
+        log.debug("Removd post tags: [{}]", postTags);
+
+        // Remove post categories
+        List<PostCategory> postCategories = postCategoryService.removeByPostId(postId);
+
+        log.debug("Removed post categories: [{}]", postCategories);
+
+        return super.removeById(postId);
+    }
+
     /**
-     * Convert to post detail vo.
+     * Converts to post detail vo.
      *
      * @param post post must not be null
      * @return post detail vo
@@ -264,7 +290,7 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
     }
 
     /**
-     * Convert to post detail vo.
+     * Converts to post detail vo.
      *
      * @param post                  post must not be null
      * @param tagIdSetSupplier      tag id set supplier
@@ -272,7 +298,7 @@ public class PostServiceImpl extends AbstractCrudService<Post, Integer> implemen
      * @return post detail vo
      */
     @NonNull
-    private PostDetailVO convertTo(@NonNull Post post, Supplier<Set<Integer>> tagIdSetSupplier, Supplier<Set<Integer>> categoryIdSetSupplier) {
+    private PostDetailVO convertTo(@NonNull Post post, @Nullable Supplier<Set<Integer>> tagIdSetSupplier, @Nullable Supplier<Set<Integer>> categoryIdSetSupplier) {
         Assert.notNull(post, "Post must not be null");
 
         PostDetailVO postDetailVO = new PostDetailVO().convertFrom(post);
diff --git a/src/main/java/cc/ryanc/halo/service/impl/PostTagServiceImpl.java b/src/main/java/cc/ryanc/halo/service/impl/PostTagServiceImpl.java
index f8e03be14..af0d3f18e 100644
--- a/src/main/java/cc/ryanc/halo/service/impl/PostTagServiceImpl.java
+++ b/src/main/java/cc/ryanc/halo/service/impl/PostTagServiceImpl.java
@@ -170,4 +170,18 @@ public class PostTagServiceImpl extends AbstractCrudService<PostTag, Integer> im
 
         return postTagRepository.findAllTagIdsByPostId(postId);
     }
+
+    @Override
+    public List<PostTag> removeByPostId(Integer postId) {
+        Assert.notNull(postId, "Post id must not be null");
+
+        return postTagRepository.deleteByPostId(postId);
+    }
+
+    @Override
+    public List<PostTag> removeByTagId(Integer tagId) {
+        Assert.notNull(tagId, "Tag id must not be null");
+
+        return postTagRepository.deleteByTagId(tagId);
+    }
 }
diff --git a/src/main/java/cc/ryanc/halo/web/controller/admin/api/PostController.java b/src/main/java/cc/ryanc/halo/web/controller/admin/api/PostController.java
index b52de55f5..17ddc182e 100644
--- a/src/main/java/cc/ryanc/halo/web/controller/admin/api/PostController.java
+++ b/src/main/java/cc/ryanc/halo/web/controller/admin/api/PostController.java
@@ -72,4 +72,9 @@ public class PostController {
         return postService.updateBy(postToUpdate, postParam.getTagIds(), postParam.getCategoryIds());
     }
 
+    @DeleteMapping("{postId:\\d+}")
+    public void deletePermanently(@PathVariable("postId") Integer postId) {
+        // Remove it
+        postService.removeById(postId);
+    }
 }