diff --git a/packages/marshal/test/test-marshal-serialization.js b/packages/marshal/test/test-marshal-serialization.js
new file mode 100644
index 0000000000..4f2f95440a
--- /dev/null
+++ b/packages/marshal/test/test-marshal-serialization.js
@@ -0,0 +1,63 @@
+import { test } from './prepare-test-env-ava.js';
+
+// eslint-disable-next-line import/order
+import { makeMarshal } from '../src/marshal.js';
+
+test('toCapData', t => {
+  const m = makeMarshal();
+  const o = harden({ a: 1 });
+
+  // deprecated seralization API
+  const usingSerializeMethod = m.serialize(o);
+
+  const usingToCapDataMethod = m.toCapData(o);
+
+  t.deepEqual(
+    usingSerializeMethod,
+    usingToCapDataMethod,
+    'should create a serialized object that is deeply equal to value produced using makeMarshal().serialize',
+  );
+
+  const oo = harden([o, o]);
+
+  const ooUsingSerializeMethod = m.serialize(oo);
+  const ooUsingToCapDataMethod = m.toCapData(oo);
+  t.deepEqual(
+    ooUsingSerializeMethod,
+    ooUsingToCapDataMethod,
+    'given a previously serialized object, should create a serialized object that is deeply equal to value produced using makeMarshal().serialize',
+  );
+});
+
+test('fromCapData', t => {
+  const m = makeMarshal();
+  const o = harden({ a: 1 });
+
+  // deprecated seralization API
+  const usingSerializeMethod = m.serialize(o);
+
+  const usingToCapDataMethod = m.toCapData(o);
+
+  const usingUnserializeMethod = m.unserialize(usingSerializeMethod);
+  const usingFromCapDataMethod = m.fromCapData(usingToCapDataMethod);
+
+  t.deepEqual(
+    usingUnserializeMethod,
+    usingFromCapDataMethod,
+    'should return an unserialized object that is deeply equal to value unserialized using makeMarshal().unserialize',
+  );
+
+  const oo = harden([o, o]);
+
+  const ooUsingSerializeMethod = m.serialize(oo);
+  const ooUsingToCapDataMethod = m.toCapData(oo);
+
+  const uoUsingUnserializeMethod = m.unserialize(ooUsingSerializeMethod);
+  const uoUsingFromCapDataMethod = m.fromCapData(ooUsingToCapDataMethod);
+
+  t.deepEqual(
+    uoUsingUnserializeMethod,
+    uoUsingFromCapDataMethod,
+    'given a previously serialized object, should create a serialized object that is deeply equal to value produced using makeMarshal().serialize',
+  );
+});