diff --git a/packages/wmr/src/plugins/worker-plugin.js b/packages/wmr/src/plugins/worker-plugin.js
index 5222c1e9..bdd2d46f 100644
--- a/packages/wmr/src/plugins/worker-plugin.js
+++ b/packages/wmr/src/plugins/worker-plugin.js
@@ -118,8 +118,9 @@ export function workerPlugin(options) {
 						}
 
 						const start = match.index + match[0].indexOf(spec);
-						// Account for quoting characters
-						s.overwrite(start - 1, start + spec.length + 1, `import.meta.ROLLUP_FILE_URL_${ref}`);
+						// Account for quoting characters and force URL to be
+						// relative.
+						s.overwrite(start - 1, start + spec.length + 1, `'.' + import.meta.ROLLUP_FILE_URL_${ref}`);
 					}
 
 					return {
diff --git a/packages/wmr/test/fixtures/worker-relative/foo/foo.worker.js b/packages/wmr/test/fixtures/worker-relative/foo/foo.worker.js
new file mode 100644
index 00000000..bd05ed84
--- /dev/null
+++ b/packages/wmr/test/fixtures/worker-relative/foo/foo.worker.js
@@ -0,0 +1,3 @@
+addEventListener('message', () => {
+	postMessage('it works');
+});
diff --git a/packages/wmr/test/fixtures/worker-relative/foo/index.js b/packages/wmr/test/fixtures/worker-relative/foo/index.js
new file mode 100644
index 00000000..5bb0e2fd
--- /dev/null
+++ b/packages/wmr/test/fixtures/worker-relative/foo/index.js
@@ -0,0 +1,7 @@
+const worker = new Worker(new URL('./foo.worker.js', import.meta.url));
+
+worker.addEventListener('message', e => {
+	document.querySelector('h1').textContent = e.data;
+});
+
+worker.postMessage('hello');
diff --git a/packages/wmr/test/fixtures/worker-relative/index.html b/packages/wmr/test/fixtures/worker-relative/index.html
new file mode 100644
index 00000000..9cfb45a0
--- /dev/null
+++ b/packages/wmr/test/fixtures/worker-relative/index.html
@@ -0,0 +1,2 @@
+<h1>it doesn't work</h1>
+<script src="./index.js" type="module"></script>
diff --git a/packages/wmr/test/fixtures/worker-relative/index.js b/packages/wmr/test/fixtures/worker-relative/index.js
new file mode 100644
index 00000000..76a6714b
--- /dev/null
+++ b/packages/wmr/test/fixtures/worker-relative/index.js
@@ -0,0 +1 @@
+import './foo/index.js';