diff --git a/.changeset/good-pandas-burn.md b/.changeset/good-pandas-burn.md
new file mode 100644
index 00000000000..1d799bc9e29
--- /dev/null
+++ b/.changeset/good-pandas-burn.md
@@ -0,0 +1,5 @@
+---
+"@remix-run/dev": patch
+---
+
+Fix validation error due to http2 pseudo headers
diff --git a/packages/remix-dev/vite/node/adapter.ts b/packages/remix-dev/vite/node/adapter.ts
index 2e6d3c57443..1d1aa7e4fac 100644
--- a/packages/remix-dev/vite/node/adapter.ts
+++ b/packages/remix-dev/vite/node/adapter.ts
@@ -67,6 +67,11 @@ function createHeaders(requestHeaders) {
   let headers = new Headers();
 
   for (let [key, values] of Object.entries(requestHeaders)) {
+    // skip http2 pseudo headers since it would cause validation error
+    // in @remix-run/web-fetch's Headers polyfill
+    if (key.startsWith(":")) {
+      continue;
+    }
     if (values) {
       if (Array.isArray(values)) {
         for (let value of values) {