diff --git a/engineio/packet.py b/engineio/packet.py
index 79267044..45349e19 100644
--- a/engineio/packet.py
+++ b/engineio/packet.py
@@ -58,6 +58,8 @@ def decode(self, encoded_packet):
         b64 = False
         if not isinstance(encoded_packet, binary_types):
             encoded_packet = encoded_packet.encode('utf-8')
+        elif not isinstance(encoded_packet, bytes):
+            encoded_packet = bytes(encoded_packet)
         self.packet_type = six.byte2int(encoded_packet[0:1])
         if self.packet_type == 98:  # 'b' --> binary base64 encoded packet
             self.binary = True