diff --git a/playground/app/providers.ts b/playground/app/providers.ts
index d80670711..0a05c307d 100644
--- a/playground/app/providers.ts
+++ b/playground/app/providers.ts
@@ -93,6 +93,12 @@ export const providers: Provider[] = [
         height: 300,
         link: 'https://unsplash.com/@omidarmin?utm_source=unsplash&utm_medium=referral&utm_content=creditCopyText',
       },
+      {
+        src: '/images/test+plus.png',
+        from: 'Filename with + (issue #1378)',
+        width: 300,
+        height: 300,
+      },
     ],
   },
   // Aliyun
diff --git a/playground/public/images/test+plus.png b/playground/public/images/test+plus.png
new file mode 100644
index 000000000..235232eae
Binary files /dev/null and b/playground/public/images/test+plus.png differ
diff --git a/src/runtime/server/routes/_ipx.ts b/src/runtime/server/routes/_ipx.ts
index defcd87cf..3add17f0d 100644
--- a/src/runtime/server/routes/_ipx.ts
+++ b/src/runtime/server/routes/_ipx.ts
@@ -31,11 +31,17 @@ export default lazyEventHandler(() => {
   const ipx = createIPX(ipxOptions)
   const nodeHandler = createIPXNodeHandler(ipx, {
     parseURL(url) {
-      const parsedURL = new URL(url)
+      const parsedURL = new URL(url, 'http://localhost')
       let pathname = parsedURL.pathname
       if (baseURL && (pathname === baseURL || pathname.startsWith(`${baseURL}/`))) {
         pathname = pathname.slice(baseURL.length) || '/'
       }
+      try {
+        pathname = decodeURI(pathname)
+      }
+      catch {
+        // Keep original pathname if decoding fails.
+      }
       return parseIPXURL(parsedURL.origin + pathname + parsedURL.search)
     },
   })
diff --git a/test/e2e/__snapshots__/ipx.json5 b/test/e2e/__snapshots__/ipx.json5
index 9ed913a9d..b601e7220 100644
--- a/test/e2e/__snapshots__/ipx.json5
+++ b/test/e2e/__snapshots__/ipx.json5
@@ -5,6 +5,7 @@
     "/_ipx/s_300x300/images/colors.jpg",
     "/_ipx/s_300x300/images/everest.jpg",
     "/_ipx/s_300x300/images/tacos.svg",
+    "/_ipx/s_300x300/images/test%2Bplus.png",
     "/_ipx/s_300x300/unsplash/photo-1606112219348-204d7d8b94ee",
   ],
   "sources": [
@@ -14,5 +15,6 @@
     "/_ipx/s_300x300/images/everest.jpg",
     "/_ipx/s_300x300/images/tacos.svg",
     "/_ipx/s_300x300/unsplash/photo-1606112219348-204d7d8b94ee",
+    "/_ipx/s_300x300/images/test%2Bplus.png",
   ],
 }
\ No newline at end of file
diff --git a/test/e2e/generate.test.ts b/test/e2e/generate.test.ts
index 4bb300721..0ab1c139f 100644
--- a/test/e2e/generate.test.ts
+++ b/test/e2e/generate.test.ts
@@ -40,12 +40,14 @@ describe('ipx provider', () => {
         "_ipx/s_300x300/images/colors.jpg",
         "_ipx/s_300x300/images/everest.jpg",
         "_ipx/s_300x300/images/tacos.svg",
+        "_ipx/s_300x300/images/test%2Bplus.png",
         "_ipx/s_300x300/unsplash/photo-1606112219348-204d7d8b94ee",
         "_ipx/s_600x600/images/colors-layer-config.jpg",
         "_ipx/s_600x600/images/colors-layer.jpg",
         "_ipx/s_600x600/images/colors.jpg",
         "_ipx/s_600x600/images/everest.jpg",
         "_ipx/s_600x600/images/tacos.svg",
+        "_ipx/s_600x600/images/test%2Bplus.png",
         "_ipx/s_600x600/unsplash/photo-1606112219348-204d7d8b94ee",
       ]
     `)