diff --git a/packages/next/server/body-streams.ts b/packages/next/server/body-streams.ts
index 7218529a660a4e..f5bd6dfe172bc7 100644
--- a/packages/next/server/body-streams.ts
+++ b/packages/next/server/body-streams.ts
@@ -3,11 +3,14 @@ import { PassThrough, Readable } from 'stream'
 
 export function requestToBodyStream(
   context: { ReadableStream: typeof ReadableStream },
+  KUint8Array: typeof Uint8Array,
   stream: Readable
 ) {
   return new context.ReadableStream({
     start(controller) {
-      stream.on('data', (chunk) => controller.enqueue(chunk))
+      stream.on('data', (chunk) =>
+        controller.enqueue(new KUint8Array([...new Uint8Array(chunk)]))
+      )
       stream.on('end', () => controller.close())
       stream.on('error', (err) => controller.error(err))
     },
diff --git a/packages/next/server/web/sandbox/fetch-inline-assets.ts b/packages/next/server/web/sandbox/fetch-inline-assets.ts
index 8c3c0ba751b11f..b017c6e8ee752b 100644
--- a/packages/next/server/web/sandbox/fetch-inline-assets.ts
+++ b/packages/next/server/web/sandbox/fetch-inline-assets.ts
@@ -34,7 +34,7 @@ export async function fetchInlineAsset(options: {
   if (fileIsReadable) {
     const readStream = createReadStream(filePath)
     return new options.context.Response(
-      requestToBodyStream(options.context, readStream)
+      requestToBodyStream(options.context, Uint8Array, readStream)
     )
   }
 }
diff --git a/packages/next/server/web/sandbox/sandbox.ts b/packages/next/server/web/sandbox/sandbox.ts
index d232294d5fceab..1d689fd0b8749a 100644
--- a/packages/next/server/web/sandbox/sandbox.ts
+++ b/packages/next/server/web/sandbox/sandbox.ts
@@ -92,11 +92,14 @@ export const run = withTaggedErrors(async (params) => {
     ? params.request.body?.cloneBodyStream()
     : undefined
 
+  const KUint8Array = runtime.evaluate('Uint8Array')
+
   try {
     const result = await edgeFunction({
       request: {
         ...params.request,
-        body: cloned && requestToBodyStream(runtime.context, cloned),
+        body:
+          cloned && requestToBodyStream(runtime.context, KUint8Array, cloned),
       },
     })
     for (const headerName of FORBIDDEN_HEADERS) {