diff --git a/src/routing.ts b/src/routing.ts
index 2cc9421eeb..73e4deea4a 100644
--- a/src/routing.ts
+++ b/src/routing.ts
@@ -7,6 +7,7 @@ import { runtimeDir } from "nitro/meta";
 import { addRoute, createRouter, findRoute, findAllRoutes } from "rou3";
 import { compileRouterToString } from "rou3/compiler";
 import { hash } from "ohash";
+import { encodeNonAsciiRoute } from "./utils/route.ts";
 
 const isGlobalMiddleware = (h: NitroEventHandler) => !h.method && (!h.route || h.route === "/**");
 
@@ -157,7 +158,12 @@ export class Router<T> {
     this._router = createRouter<T>();
     this._compiled = undefined;
     for (const route of routes) {
-      addRoute(this._router, route.method, this._baseURL + route.route, route.data);
+      addRoute(
+        this._router,
+        route.method,
+        this._baseURL + encodeNonAsciiRoute(route.route),
+        route.data
+      );
     }
     if (opts?.merge) {
       mergeCatchAll(this._router);
diff --git a/src/utils/route.ts b/src/utils/route.ts
new file mode 100644
index 0000000000..9b6c529ce5
--- /dev/null
+++ b/src/utils/route.ts
@@ -0,0 +1,16 @@
+// Percent-encodes the non-ASCII characters in a route pattern, leaving the rest untouched.
+export function encodeNonAsciiRoute(route: string): string {
+  let hasNonAscii = false;
+  for (let i = 0; i < route.length; i++) {
+    if (route.charCodeAt(i) > 127) {
+      hasNonAscii = true;
+      break;
+    }
+  }
+  if (!hasNonAscii) {
+    return route;
+  }
+  return Array.from(route)
+    .map((char) => (char.codePointAt(0)! > 127 ? encodeURIComponent(char) : char))
+    .join("");
+}
diff --git a/test/vite/nonascii-route-fixture/nitro.config.ts b/test/vite/nonascii-route-fixture/nitro.config.ts
new file mode 100644
index 0000000000..943c4ac23d
--- /dev/null
+++ b/test/vite/nonascii-route-fixture/nitro.config.ts
@@ -0,0 +1,9 @@
+import { defineConfig } from "nitro";
+
+export default defineConfig({
+  preset: "static",
+  prerender: { routes: ["/について"] },
+  // Points to an ASCII-named handler file; the route pattern itself is the literal
+  // non-ASCII text.
+  handlers: [{ route: "/について", handler: "./routes/nonascii.ts", method: "GET" }],
+});
diff --git a/test/vite/nonascii-route-fixture/routes/nonascii.ts b/test/vite/nonascii-route-fixture/routes/nonascii.ts
new file mode 100644
index 0000000000..4994d62cce
--- /dev/null
+++ b/test/vite/nonascii-route-fixture/routes/nonascii.ts
@@ -0,0 +1 @@
+export default () => "<h1>ok</h1>";
diff --git a/test/vite/nonascii-route-fixture/vite.config.ts b/test/vite/nonascii-route-fixture/vite.config.ts
new file mode 100644
index 0000000000..dc884054e6
--- /dev/null
+++ b/test/vite/nonascii-route-fixture/vite.config.ts
@@ -0,0 +1,6 @@
+import { defineConfig } from "vite";
+import { nitro } from "nitro/vite";
+
+export default defineConfig({
+  plugins: [nitro()],
+});
diff --git a/test/vite/nonascii-route.test.ts b/test/vite/nonascii-route.test.ts
new file mode 100644
index 0000000000..742fe8d036
--- /dev/null
+++ b/test/vite/nonascii-route.test.ts
@@ -0,0 +1,63 @@
+import { fileURLToPath } from "node:url";
+import { join } from "node:path";
+import { rm, mkdir, readFile } from "node:fs/promises";
+import { describe, expect, it } from "vitest";
+import { createNitro, build, prepare } from "nitro/builder";
+
+const fixtureDir = fileURLToPath(new URL("./nonascii-route-fixture", import.meta.url));
+const tmpDir = fileURLToPath(new URL("./nonascii-route-fixture/.tmp", import.meta.url));
+
+// A route path written in Japanese. Registered via `handlers` in the fixture's
+// nitro.config.ts so the route pattern stays literal Unicode without needing a
+// non-ASCII filename in the repo.
+const route = "/について";
+
+describe("non-ASCII route paths", () => {
+  it("is prerendered under its own literal path (static preset)", async () => {
+    const outDir = join(tmpDir, "static");
+    await rm(outDir, { recursive: true, force: true });
+    await mkdir(outDir, { recursive: true });
+    const nitro = await createNitro({
+      rootDir: fixtureDir,
+      preset: "static",
+      output: { dir: outDir },
+      builder: "vite",
+    });
+    try {
+      await prepare(nitro);
+      await build(nitro);
+    } finally {
+      await nitro.close();
+    }
+
+    // Reads the file prerendered at the route's own literal path.
+    const html = await readFile(join(outDir, "public", "について"), "utf8");
+    expect(html).toBe("<h1>ok</h1>");
+  }, 30_000);
+
+  it("is reachable on a running server", async () => {
+    const outDir = join(tmpDir, "standard");
+    await rm(outDir, { recursive: true, force: true });
+    await mkdir(outDir, { recursive: true });
+    const nitro = await createNitro({
+      rootDir: fixtureDir,
+      preset: "standard",
+      output: { dir: outDir },
+      builder: "vite",
+    });
+    try {
+      await prepare(nitro);
+      await build(nitro);
+    } finally {
+      await nitro.close();
+    }
+
+    const entry = join(outDir, "server/index.mjs");
+    const { fetch } = await import(entry).then((m) => m.default);
+
+    // Requests the literal Unicode path, exactly as a browser navigation would send it.
+    const response = await fetch(new Request(`http://localhost${route}`));
+    expect(response.status).toBe(200);
+    expect(await response.text()).toBe("<h1>ok</h1>");
+  }, 30_000);
+});