diff --git a/README.md b/README.md
index 4a1b6d4..a19f98e 100644
--- a/README.md
+++ b/README.md
@@ -88,8 +88,10 @@ marked:
   ```
   * `![text](/path/to/image.jpg)` becomes `<img src="/blog/path/to/image.jpg" alt="text">`
 - **postAsset** - Resolve post asset's image path to relative path and prepend root value when [`post_asset_folder`](https://hexo.io/docs/asset-folders) is enabled.
-  * "image.jpg" is located at "/2020/01/02/foo/image.jpg", which is a post asset of "/2020/01/02/foo/".
-  * `![](image.jpg)` becomes `<img src="/2020/01/02/foo/image.jpg">`
+  * Search for assets first in the post asset folder, then the parent folder of the post asset folder. The search process is aborted once the image is found.
+  * "image.jpg" is located at "/2020/01/02/foo/image.jpg" and locally `source/_post/foo/image.jpg` , which is a post asset of "/2020/01/02/foo/".
+  * `![](image.jpg)` becomes `<img src="/2020/01/02/foo/image.jpg">` (asset is found in post asset folder since `source/_post/foo` `/` `image.jpg` exists.)
+  * `![](foo/image.jpg)` also becomes `<img src="/2020/01/02/foo/image.jpg">` (asset is found in the parent folder of post asset folder since `source/_post` `/` `foo/image.jpg` exists.)
   * Requires **prependRoot** to be enabled.
 - **external_link**
   * **enable** - Open external links in a new tab.
diff --git a/lib/renderer.js b/lib/renderer.js
index e16894b..c37967c 100644
--- a/lib/renderer.js
+++ b/lib/renderer.js
@@ -136,14 +136,22 @@ const renderer = {
     const { hexo } = options;
     const { relative_link } = hexo.config;
     const { lazyload, figcaption, prependRoot, postPath } = options;
+    const searchAssetLocation = ['./', '../'];
 
     if (!/^(#|\/\/|http(s)?:)/.test(href) && !relative_link && prependRoot) {
       if (!href.startsWith('/') && !href.startsWith('\\') && postPath) {
         const PostAsset = hexo.model('PostAsset');
-        // findById requires forward slash
-        const asset = PostAsset.findById(join(postPath, href.replace(/\\/g, '/')));
-        // asset.path is backward slash in Windows
-        if (asset) href = asset.path.replace(/\\/g, '/');
+        for (const appendPath of searchAssetLocation) {
+          const destPath = join(postPath, appendPath);
+          // findById requires forward slash
+          const asset = PostAsset.findById(join(destPath, href.replace(/\\/g, '/')));
+          // asset.path is backward slash in Windows
+          if (asset) {
+            href = asset.path.replace(/\\/g, '/');
+            // asset is found, stop searching
+            break;
+          }
+        }
       }
       href = url_for.call(hexo, href);
     }
@@ -217,7 +225,7 @@ const tokenizer = {
   }
 };
 
-module.exports = function(data, options) {
+module.exports = function (data, options) {
   const { post_asset_folder, marked: markedCfg, source_dir } = this.config;
   const { prependRoot, postAsset, dompurify } = markedCfg;
   const { path, text } = data;
@@ -247,7 +255,7 @@ module.exports = function(data, options) {
     }
   }
 
-  let sanitizer = function(html) { return html; };
+  let sanitizer = function (html) { return html; };
 
   if (dompurify) {
     if (createDOMPurify === undefined && JSDOM === undefined) {
@@ -260,7 +268,7 @@ module.exports = function(data, options) {
     if (dompurify !== true) {
       param = dompurify;
     }
-    sanitizer = function(html) { return DOMPurify.sanitize(html, param); };
+    sanitizer = function (html) { return DOMPurify.sanitize(html, param); };
   }
 
   marked.use({