diff --git a/imbox/parser.py b/imbox/parser.py
index 9d83fe3..bed6886 100644
--- a/imbox/parser.py
+++ b/imbox/parser.py
@@ -71,7 +71,7 @@ def decode_param(param):
             if type_ == 'Q':
                 value = quopri.decodestring(code)
             elif type_ == 'B':
-                value = base64.decodestring(code)
+                value = base64.decodebytes(code.encode())
             value = str_encode(value, encoding)
             value_results.append(value)
             if value_results:
diff --git a/tests/parser_tests.py b/tests/parser_tests.py
index 7d1fba7..b642d44 100644
--- a/tests/parser_tests.py
+++ b/tests/parser_tests.py
@@ -82,6 +82,46 @@ Content-Transfer-Encoding: quoted-printable
 """
 
 
+raw_email_encoded_bad_multipart = b"""Delivered-To: receiver@example.com
+Return-Path: <sender@example.com>
+From: sender@example.com
+To: "Receiver" <receiver@example.com>, "Second\r\n Receiver" <recipient@example.com>
+Subject: Re: Looking to connect with you...
+Date: Thu, 20 Apr 2017 15:32:52 +0000
+Message-ID: <BN6PR16MB179579288933D60C4016D078C31B0@BN6PR16MB1795.namprd16.prod.outlook.com>
+Content-Type: multipart/related;
+	boundary="_004_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_";
+	type="multipart/alternative"
+MIME-Version: 1.0
+--_004_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_
+Content-Type: multipart/alternative;
+	boundary="_000_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_"
+--_000_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_
+Content-Type: text/plain; charset="utf-8"
+Content-Transfer-Encoding: base64
+SGkgRGFuaWVsbGUsDQoNCg0KSSBhY3R1YWxseSBhbSBoYXBweSBpbiBteSBjdXJyZW50IHJvbGUs
+Y3J1aXRlciB8IENoYXJsb3R0ZSwgTkMNClNlbnQgdmlhIEhhcHBpZQ0KDQoNCg==
+--_000_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_
+Content-Type: text/html; charset="utf-8"
+Content-Transfer-Encoding: base64
+PGh0bWw+DQo8aGVhZD4NCjxtZXRhIGh0dHAtZXF1aXY9IkNvbnRlbnQtVHlwZSIgY29udGVudD0i
+CjwvZGl2Pg0KPC9kaXY+DQo8L2JvZHk+DQo8L2h0bWw+DQo=
+--_000_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_--
+--_004_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_
+Content-Type: image/png; name="=?utf-8?B?T3V0bG9va0Vtb2ppLfCfmIoucG5n?="
+Content-Description: =?utf-8?B?T3V0bG9va0Vtb2ppLfCfmIoucG5n?=
+Content-Disposition: inline;
+	filename="=?utf-8?B?T3V0bG9va0Vtb2ppLfCfmIoucG5n?="; size=488;
+	creation-date="Thu, 20 Apr 2017 15:32:52 GMT";
+	modification-date="Thu, 20 Apr 2017 15:32:52 GMT"
+Content-ID: <254962e2-f05c-40d1-aa11-0d34671b056c>
+Content-Transfer-Encoding: base64
+iVBORw0KGgoAAAANSUhEUgAAABMAAAATCAYAAAByUDbMAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJ
+cvED9AIR3TCAAAMAqh+p+YMVeBQAAAAASUVORK5CYII=
+--_004_BN6PR16MB179579288933D60C4016D078C31B0BN6PR16MB1795namp_--
+"""
+
+
 class TestParser(unittest.TestCase):
 
     def test_parse_email(self):
@@ -98,6 +138,10 @@ class TestParser(unittest.TestCase):
         self.assertEqual('Выписка по карте', parsed_email.subject)
         self.assertEqual('Выписка по карте 1234', parsed_email.body['html'][0])
 
+    def test_parse_email_bad_multipart(self):
+        parsed_email = parse_email(raw_email_encoded_bad_multipart)
+        self.assertEqual("Re: Looking to connect with you...", parsed_email.subject)
+
     def test_parse_email_ignores_header_casing(self):
         self.assertEqual('one', parse_email('Message-ID: one').message_id)
         self.assertEqual('one', parse_email('Message-Id: one').message_id)