diff --git a/src/js_printer.zig b/src/js_printer.zig
index 09b3bfdbbf8d4..486f94e23bb50 100644
--- a/src/js_printer.zig
+++ b/src/js_printer.zig
@@ -6036,7 +6036,8 @@ pub fn printWithWriterAndPlatform(
     comptime generate_source_maps: bool,
 ) PrintResult {
     const PrinterType = NewPrinter(
-        false,
+        // if it's bun, it is also ascii_only
+        is_bun_platform,
         Writer,
         false,
         is_bun_platform,
diff --git a/test/regression/issue/09559.test.ts b/test/regression/issue/09559.test.ts
new file mode 100644
index 0000000000000..329033b584a29
--- /dev/null
+++ b/test/regression/issue/09559.test.ts
@@ -0,0 +1,22 @@
+import { $ } from "bun";
+import { expect, test } from "bun:test";
+import { bunEnv, bunExe, tempDirWithFiles } from "harness";
+import { readdirSync } from "node:fs";
+import { join } from "path";
+
+test("bun build --target bun should support non-ascii source", async () => {
+  const files = {"index.js": `
+    console.log(JSON.stringify({我: "a"}));
+
+    const 我 = "b";
+    console.log(JSON.stringify({我}));
+  `};
+  const filenames = Object.keys(files);
+  const source = tempDirWithFiles("source", files);
+
+  $.throws(true);
+  await $`${bunExe()} build --target bun ${join(source, "index.js")} --outfile ${join(source, "bundle.js")}`;
+  const result = await $`${bunExe()} ${join(source, "bundle.js")}`.text();
+  
+  expect(result).toBe(`{"我":"a"}\n{"我":"b"}\n`);
+})