diff --git a/packages/vite/src/node/optimizer/index.ts b/packages/vite/src/node/optimizer/index.ts
index 13c322610cf493..3828cb2fbce18b 100644
--- a/packages/vite/src/node/optimizer/index.ts
+++ b/packages/vite/src/node/optimizer/index.ts
@@ -417,11 +417,12 @@ export async function runOptimizeDeps(
       try {
         exportsData = parse(entryContent) as ExportsData
       } catch {
+        const loader = esbuildOptions.loader?.[path.extname(filePath)] || 'jsx'
         debug(
-          `Unable to parse dependency: ${id}. Trying again with a JSX transform.`
+          `Unable to parse dependency: ${id}. Trying again with a ${loader} transform.`
         )
         const transformed = await transformWithEsbuild(entryContent, filePath, {
-          loader: 'jsx'
+          loader
         })
         // Ensure that optimization won't fail by defaulting '.js' to the JSX parser.
         // This is useful for packages such as Gatsby.
diff --git a/packages/vite/src/node/optimizer/scan.ts b/packages/vite/src/node/optimizer/scan.ts
index e940617386eb35..ef59a35b1d22d3 100644
--- a/packages/vite/src/node/optimizer/scan.ts
+++ b/packages/vite/src/node/optimizer/scan.ts
@@ -463,21 +463,26 @@ function esbuildScanPlugin(
           contents = config.esbuild.jsxInject + `\n` + contents
         }
 
+        const loader =
+          config.optimizeDeps?.esbuildOptions?.loader?.[`.${ext}`] ||
+          (ext as Loader)
+
         if (contents.includes('import.meta.glob')) {
           return transformGlob(
             contents,
             id,
             config.root,
-            ext as Loader,
+            loader,
             resolve,
             config.logger
           ).then((contents) => ({
-            loader: ext as Loader,
+            loader,
             contents
           }))
         }
+
         return {
-          loader: ext as Loader,
+          loader,
           contents
         }
       })