diff --git a/.changeset/fix-preview-props-manifest.md b/.changeset/fix-preview-props-manifest.md
new file mode 100644
index 000000000..e21db1012
--- /dev/null
+++ b/.changeset/fix-preview-props-manifest.md
@@ -0,0 +1,14 @@
+---
+"@opennextjs/cloudflare": patch
+---
+
+fix(patches): include `preview-props.json` in loadManifest build-time inlining
+
+Next.js 16.4 moved preview props out of `prerender-manifest.json` into a standalone
+`.next/server/preview-props.json` (`PREVIEW_PROPS_MANIFEST`), loaded unconditionally by
+`NextNodeServer.getPreviewProps()` from the `Server` constructor. The file exists in the build
+output but wasn't matched by the glob pattern `*-manifest.json`, so the patched `loadManifest()`
+threw at runtime and every dynamic route returned a 500.
+
+It is inlined rather than falling back to `{}` because it holds the actual draft-mode
+id and signing/encryption keys.
diff --git a/packages/cloudflare/src/cli/build/patches/plugins/load-manifest.ts b/packages/cloudflare/src/cli/build/patches/plugins/load-manifest.ts
index 143dd544f..fa8907346 100644
--- a/packages/cloudflare/src/cli/build/patches/plugins/load-manifest.ts
+++ b/packages/cloudflare/src/cli/build/patches/plugins/load-manifest.ts
@@ -39,8 +39,13 @@ async function getLoadManifestRule(buildOpts: BuildOptions) {
 	const baseDir = join(outputDir, "server-functions/default", getPackagePath(buildOpts));
 	const dotNextDir = join(baseDir, ".next");
 
+	// Most server manifests are named `*-manifest.json`, but a few are not:
+	// `required-server-files.json`, `prefetch-hints.json` (Next 16.2+) and
+	// `server/preview-props.json` (Next 16.4+, previously inlined in the
+	// prerender manifest). They are loaded unconditionally by `NextNodeServer`,
+	// so they must be inlined rather than falling back to `{}`.
 	const manifests = await glob(
-		join(dotNextDir, "**/{*-manifest,required-server-files,prefetch-hints}.json"),
+		join(dotNextDir, "**/{*-manifest,required-server-files,prefetch-hints,preview-props}.json"),
 		{
 			windowsPathsNoEscape: true,
 		}