diff --git a/packages/vite/src/node/server/middlewares/indexHtml.ts b/packages/vite/src/node/server/middlewares/indexHtml.ts
index 9213b59e11417e..b5893dd072b972 100644
--- a/packages/vite/src/node/server/middlewares/indexHtml.ts
+++ b/packages/vite/src/node/server/middlewares/indexHtml.ts
@@ -191,7 +191,7 @@ const devHtmlHook: IndexHtmlTransformHook = async (
   const trailingSlash = htmlPath.endsWith('/')
   if (!trailingSlash && getFsUtils(config).existsSync(filename)) {
     proxyModulePath = htmlPath
-    proxyModuleUrl = joinUrlSegments(base, htmlPath)
+    proxyModuleUrl = proxyModulePath
   } else {
     // There are users of vite.transformIndexHtml calling it with url '/'
     // for SSR integrations #7993, filename is root for this case
@@ -200,8 +200,9 @@ const devHtmlHook: IndexHtmlTransformHook = async (
     // and ids are properly handled
     const validPath = `${htmlPath}${trailingSlash ? 'index.html' : ''}`
     proxyModulePath = `\0${validPath}`
-    proxyModuleUrl = joinUrlSegments(base, wrapId(proxyModulePath))
+    proxyModuleUrl = wrapId(proxyModulePath)
   }
+  proxyModuleUrl = joinUrlSegments(base, proxyModuleUrl)
 
   const s = new MagicString(html)
   let inlineModuleIndex = -1