diff --git a/src/main/java/cc/ryanc/halo/model/entity/Comment.java b/src/main/java/cc/ryanc/halo/model/entity/Comment.java
index 0810d1e6a..175fd953a 100644
--- a/src/main/java/cc/ryanc/halo/model/entity/Comment.java
+++ b/src/main/java/cc/ryanc/halo/model/entity/Comment.java
@@ -103,6 +103,10 @@ public class Comment extends BaseEntity {
     public void prePersist() {
         super.prePersist();
         id = null;
+
+        if (parentId == null || parentId < 0) {
+            parentId = 0L;
+        }
     }
 
 }
diff --git a/src/main/java/cc/ryanc/halo/model/enums/BlogProperties.java b/src/main/java/cc/ryanc/halo/model/enums/BlogProperties.java
index df624b05c..f320b7228 100644
--- a/src/main/java/cc/ryanc/halo/model/enums/BlogProperties.java
+++ b/src/main/java/cc/ryanc/halo/model/enums/BlogProperties.java
@@ -165,7 +165,7 @@ public enum BlogProperties implements ValueEnum<String> {
     private Class<?> type;
 
     BlogProperties(String value, Class<?> type) {
-        if (!supportType(type)) {
+        if (!isSupportedType(type)) {
             throw new IllegalArgumentException("Unsupported blog property type: " + type);
         }
 
@@ -199,7 +199,7 @@ public enum BlogProperties implements ValueEnum<String> {
     public static <T> T convertTo(@NonNull String value, @NonNull Class<T> type) {
         Assert.hasText(value, "Property value must not be blank");
 
-        if (!supportType(type)) {
+        if (!isSupportedType(type)) {
             throw new IllegalArgumentException("Unsupported blog property type: " + type);
         }
 
@@ -245,7 +245,7 @@ public enum BlogProperties implements ValueEnum<String> {
      * @param type type to check
      * @return true if supports; false else
      */
-    public static boolean supportType(Class<?> type) {
+    public static boolean isSupportedType(Class<?> type) {
         return type != null && (
                 type.isAssignableFrom(String.class)
                         || type.isAssignableFrom(Number.class)
diff --git a/src/main/java/cc/ryanc/halo/service/CommentService.java b/src/main/java/cc/ryanc/halo/service/CommentService.java
index 94f22cc40..46a4b5999 100644
--- a/src/main/java/cc/ryanc/halo/service/CommentService.java
+++ b/src/main/java/cc/ryanc/halo/service/CommentService.java
@@ -2,6 +2,7 @@ package cc.ryanc.halo.service;
 
 import cc.ryanc.halo.model.entity.Comment;
 import cc.ryanc.halo.model.enums.CommentStatus;
+import cc.ryanc.halo.model.params.CommentParam;
 import cc.ryanc.halo.model.vo.CommentVO;
 import cc.ryanc.halo.service.base.CrudService;
 import org.springframework.data.domain.Page;
@@ -9,6 +10,7 @@ import org.springframework.data.domain.Pageable;
 import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 
+import javax.servlet.http.HttpServletRequest;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
@@ -20,6 +22,13 @@ import java.util.Map;
  */
 public interface CommentService extends CrudService<Comment, Long> {
 
+    /**
+     * %d: parent commentator id
+     * %s: parent commentator author name
+     * %s: comment content
+     */
+    String COMMENT_TEMPLATE = "<a href='#comment-id-%d>@%s</a> %s";
+
     /**
      * Lists latest comments.
      *
@@ -49,11 +58,21 @@ public interface CommentService extends CrudService<Comment, Long> {
     List<Comment> listBy(@NonNull Integer postId);
 
     /**
-     * Count by post id collection.
+     * Counts 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);
+
+    /**
+     * Creates a comment by comment param.
+     *
+     * @param commentParam comment param must not be null and should be validated
+     * @param request      http servlet request must not be null
+     * @return created comment
+     */
+    @NonNull
+    Comment createBy(@NonNull CommentParam commentParam, @NonNull HttpServletRequest request);
 }
diff --git a/src/main/java/cc/ryanc/halo/service/impl/CommentServiceImpl.java b/src/main/java/cc/ryanc/halo/service/impl/CommentServiceImpl.java
index b4f1d95ab..868dd1f9d 100644
--- a/src/main/java/cc/ryanc/halo/service/impl/CommentServiceImpl.java
+++ b/src/main/java/cc/ryanc/halo/service/impl/CommentServiceImpl.java
@@ -1,23 +1,35 @@
 package cc.ryanc.halo.service.impl;
 
+import cc.ryanc.halo.exception.NotFoundException;
 import cc.ryanc.halo.model.dto.post.PostMinimalOutputDTO;
 import cc.ryanc.halo.model.entity.Comment;
 import cc.ryanc.halo.model.entity.Post;
+import cc.ryanc.halo.model.enums.BlogProperties;
 import cc.ryanc.halo.model.enums.CommentStatus;
+import cc.ryanc.halo.model.params.CommentParam;
 import cc.ryanc.halo.model.projection.CommentCountProjection;
 import cc.ryanc.halo.model.vo.CommentVO;
 import cc.ryanc.halo.repository.CommentRepository;
 import cc.ryanc.halo.repository.PostRepository;
 import cc.ryanc.halo.service.CommentService;
+import cc.ryanc.halo.service.OptionService;
 import cc.ryanc.halo.service.base.AbstractCrudService;
+import cc.ryanc.halo.utils.OwoUtil;
 import cc.ryanc.halo.utils.ServiceUtils;
+import cn.hutool.core.util.URLUtil;
+import cn.hutool.crypto.SecureUtil;
+import cn.hutool.extra.servlet.ServletUtil;
+import lombok.extern.slf4j.Slf4j;
+import org.apache.commons.lang3.StringUtils;
 import org.springframework.data.domain.*;
 import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 import org.springframework.stereotype.Service;
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
+import org.springframework.web.util.HtmlUtils;
 
+import javax.servlet.http.HttpServletRequest;
 import java.util.*;
 import java.util.stream.Collectors;
 
@@ -27,6 +39,7 @@ import java.util.stream.Collectors;
  * @author : RYAN0UP
  * @date : 2019-03-14
  */
+@Slf4j
 @Service
 public class CommentServiceImpl extends AbstractCrudService<Comment, Long> implements CommentService {
 
@@ -34,11 +47,15 @@ public class CommentServiceImpl extends AbstractCrudService<Comment, Long> imple
 
     private final PostRepository postRepository;
 
+    private final OptionService optionService;
+
     public CommentServiceImpl(CommentRepository commentRepository,
-                              PostRepository postRepository) {
+                              PostRepository postRepository,
+                              OptionService optionService) {
         super(commentRepository);
         this.commentRepository = commentRepository;
         this.postRepository = postRepository;
+        this.optionService = optionService;
     }
 
     @Override
@@ -81,6 +98,64 @@ public class CommentServiceImpl extends AbstractCrudService<Comment, Long> imple
         return ServiceUtils.convertToMap(commentCountProjections, CommentCountProjection::getPostId, CommentCountProjection::getCount);
     }
 
+    @Override
+    public Comment createBy(CommentParam commentParam, HttpServletRequest request) {
+        Assert.notNull(commentParam, "Comment param must not be null");
+        Assert.notNull(request, "Http servlet request must not be null");
+
+        // Post id must exist
+        boolean postExist = postRepository.existsById(commentParam.getPostId());
+        if (!postExist) {
+            log.error("Post: [{}] was not found", commentParam.getPostId());
+            throw new NotFoundException("The post was not found").setErrorData(commentParam.getPostId());
+        }
+
+        // Convert to comment
+        Comment comment = commentParam.convertTo();
+
+        // Set some default value
+        comment.setIpAddress(ServletUtil.getClientIP(request));
+        // TODO Check user login status and set this field
+        comment.setIsAdmin(false);
+        comment.setAuthor(HtmlUtils.htmlEscape(comment.getAuthor()));
+        comment.setGavatarMd5(SecureUtil.md5(comment.getEmail()));
+
+        if (comment.getParentId() != null && comment.getParentId() > 0) {
+            // Validate the comment parent id
+            Comment parentComment = getById(comment.getParentId());
+
+            // Format content and set it
+            String formattedContent = String.format(COMMENT_TEMPLATE,
+                    parentComment.getId(),
+                    parentComment.getAuthor(),
+                    OwoUtil.parseOwo(formatContent(comment.getContent())));
+            comment.setContent(formattedContent);
+        } else {
+            comment.setParentId(0L);
+            // Top comment
+            comment.setContent(OwoUtil.parseOwo(formatContent(comment.getContent())));
+        }
+
+        if (StringUtils.isNotBlank(comment.getAuthorUrl())) {
+            // Normalize the author url and set it
+            comment.setAuthorUrl(URLUtil.normalize(comment.getAuthorUrl()));
+        }
+
+        // Handle comment status
+        Boolean needAudit = optionService.getByProperty(BlogProperties.NEW_COMMENT_NEED_CHECK, Boolean.class, true);
+        if (needAudit) {
+            comment.setStatus(CommentStatus.AUDITING);
+        } else {
+            comment.setStatus(CommentStatus.PUBLISHED);
+        }
+
+        Comment createdComment = create(comment);
+
+        // TODO Handle email sending
+
+        return createdComment;
+    }
+
     /**
      * Converts to comment vo page.
      *
@@ -122,4 +197,9 @@ public class CommentServiceImpl extends AbstractCrudService<Comment, Long> imple
             return commentVO;
         }).collect(Collectors.toList());
     }
+
+    private String formatContent(@NonNull String content) {
+        return HtmlUtils.htmlEscape(content).replace("&lt;br/&gt;", "<br/>");
+    }
+
 }
diff --git a/src/main/java/cc/ryanc/halo/web/controller/admin/api/CommentController.java b/src/main/java/cc/ryanc/halo/web/controller/admin/api/CommentController.java
index dade4695d..c34905ccc 100644
--- a/src/main/java/cc/ryanc/halo/web/controller/admin/api/CommentController.java
+++ b/src/main/java/cc/ryanc/halo/web/controller/admin/api/CommentController.java
@@ -1,21 +1,16 @@
 package cc.ryanc.halo.web.controller.admin.api;
 
 import cc.ryanc.halo.model.dto.CommentOutputDTO;
-import cc.ryanc.halo.model.entity.Comment;
-import cc.ryanc.halo.model.enums.BlogProperties;
 import cc.ryanc.halo.model.enums.CommentStatus;
 import cc.ryanc.halo.model.params.CommentParam;
-import cc.ryanc.halo.model.support.HaloConst;
 import cc.ryanc.halo.model.vo.CommentVO;
 import cc.ryanc.halo.service.CommentService;
-import cc.ryanc.halo.utils.HaloUtils;
-import cn.hutool.crypto.SecureUtil;
-import cn.hutool.extra.servlet.ServletUtil;
+import cc.ryanc.halo.service.OptionService;
+import cc.ryanc.halo.service.PostService;
 import io.swagger.annotations.ApiOperation;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.web.PageableDefault;
-import org.springframework.web.bind.ServletRequestUtils;
 import org.springframework.web.bind.annotation.*;
 
 import javax.servlet.http.HttpServletRequest;
@@ -36,8 +31,16 @@ public class CommentController {
 
     private final CommentService commentService;
 
-    public CommentController(CommentService commentService) {
+    private final PostService postService;
+
+    private final OptionService optionService;
+
+    public CommentController(CommentService commentService,
+                             PostService postService,
+                             OptionService optionService) {
         this.commentService = commentService;
+        this.postService = postService;
+        this.optionService = optionService;
     }
 
     @GetMapping("latest")
@@ -54,14 +57,6 @@ public class CommentController {
 
     @PostMapping
     public CommentOutputDTO createBy(@Valid @RequestBody CommentParam commentParam, HttpServletRequest request) {
-        Comment comment = commentParam.convertTo();
-
-        // Set some default value
-        comment.setGavatarMd5(SecureUtil.md5(comment.getEmail()));
-        comment.setIpAddress(ServletUtil.getClientIP(request));
-
-
-//        commentService.createBy(comment)
-        return null;
+        return new CommentOutputDTO().convertFrom(commentService.createBy(commentParam, request));
     }
 }