diff --git a/src/main/java/run/halo/app/service/ThemeService.java b/src/main/java/run/halo/app/service/ThemeService.java
index 4cb95b388..c399b794f 100644
--- a/src/main/java/run/halo/app/service/ThemeService.java
+++ b/src/main/java/run/halo/app/service/ThemeService.java
@@ -90,4 +90,11 @@ public interface ThemeService {
      * @param content      new content
      */
     void saveTemplateContent(String absolutePath, String content);
+
+    /**
+     * Delete a theme by key.
+     *
+     * @param key theme key
+     */
+    void deleteTheme(String key);
 }
diff --git a/src/main/java/run/halo/app/service/impl/ThemeServiceImpl.java b/src/main/java/run/halo/app/service/impl/ThemeServiceImpl.java
index aa114c6c0..b4e2a0510 100644
--- a/src/main/java/run/halo/app/service/impl/ThemeServiceImpl.java
+++ b/src/main/java/run/halo/app/service/impl/ThemeServiceImpl.java
@@ -1,5 +1,6 @@
 package run.halo.app.service.impl;
 
+import cn.hutool.core.io.FileUtil;
 import cn.hutool.core.io.file.FileReader;
 import cn.hutool.core.io.file.FileWriter;
 import cn.hutool.core.text.StrBuilder;
@@ -239,4 +240,16 @@ public class ThemeServiceImpl implements ThemeService {
         final FileWriter fileWriter = new FileWriter(absolutePath);
         fileWriter.write(content);
     }
+
+    /**
+     * Delete a theme by key.
+     *
+     * @param key theme key
+     */
+    @Override
+    public void deleteTheme(String key) {
+        File file = new File(this.getThemeBasePath(),key);
+        FileUtil.del(file);
+        HaloConst.THEMES = this.getThemes();
+    }
 }
diff --git a/src/main/java/run/halo/app/web/controller/admin/api/ThemeController.java b/src/main/java/run/halo/app/web/controller/admin/api/ThemeController.java
index a0a2db873..c34bcf4e6 100644
--- a/src/main/java/run/halo/app/web/controller/admin/api/ThemeController.java
+++ b/src/main/java/run/halo/app/web/controller/admin/api/ThemeController.java
@@ -74,12 +74,12 @@ public class ThemeController {
     }
 
     @GetMapping("files/custom")
-    public List<String> customTemplate(){
+    public List<String> customTemplate() {
         return themeService.getCustomTpl(HaloConst.ACTIVATED_THEME_NAME);
     }
 
     /**
-     * Active theme
+     * Active theme.
      *
      * @param theme theme name
      * @throws TemplateModelException TemplateModelException
@@ -95,4 +95,15 @@ public class ThemeController {
         configuration.setSharedVariable("themeName", theme);
         configuration.setSharedVariable("options", optionService.listOptions());
     }
+
+    /**
+     * Deletes a theme.
+     *
+     * @param key theme key
+     */
+    @DeleteMapping("{key}")
+    @ApiOperation("Deletes a theme")
+    public void deleteBy(@PathVariable("key") String key) {
+        themeService.deleteTheme(key);
+    }
 }