diff --git a/.changeset/normalize-headers-node-consumers.md b/.changeset/normalize-headers-node-consumers.md
new file mode 100644
index 0000000000..9a817fd5bb
--- /dev/null
+++ b/.changeset/normalize-headers-node-consumers.md
@@ -0,0 +1,6 @@
+---
+'@modelcontextprotocol/sdk': patch
+---
+
+`normalizeHeaders` no longer references the DOM-only global `HeadersInit` in its published declaration. It now uses `RequestInit['headers']`, which `@types/node` binds globally, so Node-only consumers compiling with `skipLibCheck: false` and no `"DOM"` lib no longer fail with
+`TS2304: Cannot find name 'HeadersInit'`. Fixes #2568
diff --git a/src/shared/transport.ts b/src/shared/transport.ts
index f9b21bed32..18a2d669cc 100644
--- a/src/shared/transport.ts
+++ b/src/shared/transport.ts
@@ -3,10 +3,10 @@ import { JSONRPCMessage, MessageExtraInfo, RequestId } from '../types.js';
 export type FetchLike = (url: string | URL, init?: RequestInit) => Promise<Response>;
 
 /**
- * Normalizes HeadersInit to a plain Record<string, string> for manipulation.
- * Handles Headers objects, arrays of tuples, and plain objects.
+ * Normalizes header init (Headers instance, array of tuples, or plain object)
+ * to a plain Record<string, string> for manipulation.
  */
-export function normalizeHeaders(headers: HeadersInit | undefined): Record<string, string> {
+export function normalizeHeaders(headers: RequestInit['headers'] | undefined): Record<string, string> {
     if (!headers) return {};
 
     if (headers instanceof Headers) {