diff --git a/letsencrypt/client/tests/crypto_util_test.py b/letsencrypt/client/tests/crypto_util_test.py
index cb047281f..f24dbb08e 100644
--- a/letsencrypt/client/tests/crypto_util_test.py
+++ b/letsencrypt/client/tests/crypto_util_test.py
@@ -68,6 +68,40 @@ class MakeKeyTest(unittest.TestCase):  # pylint: disable=too-few-public-methods
         M2Crypto.RSA.load_key_string(make_key(4096))
 
 
+class MakeCSRTest(unittest.TestCase):
+    # pylint: disable=too-few-public-methods,bad-continuation
+    """Tests for letsencrypt.client.crypto_util.make_csr."""
+    def test_make_csr(self):
+        from letsencrypt.client.crypto_util import make_csr
+        result = make_csr(RSA512_KEY, ["example.com", "foo.example.com"])
+        self.assertEqual(
+            result, (
+"""-----BEGIN CERTIFICATE REQUEST-----
+MIIBbjCCARgCAQAweTELMAkGA1UEBhMCVVMxETAPBgNVBAgTCE1pY2hpZ2FuMRIw
+EAYDVQQHEwlBbm4gQXJib3IxDDAKBgNVBAoTA0VGRjEfMB0GA1UECxMWVW5pdmVy
+c2l0eSBvZiBNaWNoaWdhbjEUMBIGA1UEAxMLZXhhbXBsZS5jb20wXDANBgkqhkiG
+9w0BAQEFAANLADBIAkEA9LYRcVE3Nr+qleecEcX8JwVDnjeG1X7ucsCasuuZM0e0
+9cmYuUzxIkMjO/9x4AVcvXXRXPEV+LzWWkfkTlzRMwIDAQABoDowOAYJKoZIhvcN
+AQkOMSswKTAnBgNVHREEIDAeggtleGFtcGxlLmNvbYIPZm9vLmV4YW1wbGUuY29t
+MA0GCSqGSIb3DQEBCwUAA0EAAkBBkne4LNwBaZ95i1qez4Ii4nuj4Y0MaYrOe6lh
+YdCQq5RRHEKCFwxcJSZQaWWwmfbR0C2E2H7SnEPrcn4Y8w==
+-----END CERTIFICATE REQUEST-----
+""",
+            "3082016e308201180201003079310b30090603550406130255533111300f"
+            "060355040813084d6963686967616e3112301006035504071309416e6e20"
+            "4172626f72310c300a060355040a1303454646311f301d060355040b1316"
+            "556e6976657273697479206f66204d6963686967616e3114301206035504"
+            "03130b6578616d706c652e636f6d305c300d06092a864886f70d01010105"
+            "00034b003048024100f4b61171513736bfaa95e79c11c5fc2705439e3786"
+            "d57eee72c09ab2eb993347b4f5c998b94cf12243233bff71e0055cbd75d1"
+            "5cf115f8bcd65a47e44e5cd1330203010001a03a303806092a864886f70d"
+            "01090e312b302930270603551d110420301e820b6578616d706c652e636f"
+            "6d820f666f6f2e6578616d706c652e636f6d300d06092a864886f70d0101"
+            "0b05000341000240419277b82cdc01699f798b5a9ecf8222e27ba3e18d0c"
+            "698ace7ba96161d090ab94511c4282170c5c2526506965b099f6d1d02d84"
+            "d87ed29c43eb727e18f3".decode("hex")))
+
+
 class ValidPrivkeyTest(unittest.TestCase):
     """Tests for letsencrypt.client.crypto_util.valid_privkey."""