diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py
--- a/Lib/test/test_email/test_email.py
+++ b/Lib/test/test_email/test_email.py
@@ -552,6 +552,15 @@
         msg._payload = x
         self.assertEqual(msg.get_payload(decode=True), x)
 
+    def test_binary_quopri_payload(self):
+        # Although not documented, this is supposed to work.
+        msg = Message()
+        msg['content-type'] = 'text/plain; charset=latin-1'
+        msg['content-transfer-encoding'] = 'quoted-printable'
+        msg.set_payload(b'foo=e6=96=87bar')
+        self.assertEqual(msg.get_payload(decode=True),
+                        b'foo\xe6\x96\x87bar')
+
     # Issue 1078919
     def test_ascii_add_header(self):
         msg = Message()