diff --git a/serial/rfc2217.py b/serial/rfc2217.py
index 12636d46..58fb1cd4 100644
--- a/serial/rfc2217.py
+++ b/serial/rfc2217.py
@@ -463,7 +463,7 @@ def open(self):
         self.is_open = True
         self._thread = threading.Thread(target=self._telnet_read_loop)
         self._thread.daemon = True
-        self._thread.setName('pySerial RFC 2217 reader thread for {}'.format(self._port))
+        self._thread.name = 'pySerial RFC 2217 reader thread for {}'.format(self._port)
         self._thread.start()
 
         try:    # must clean-up if open fails
diff --git a/serial/urlhandler/protocol_cp2110.py b/serial/urlhandler/protocol_cp2110.py
index ce5b037c..620162f0 100644
--- a/serial/urlhandler/protocol_cp2110.py
+++ b/serial/urlhandler/protocol_cp2110.py
@@ -100,7 +100,7 @@ def open(self):
             self.is_open = True
             self._thread = threading.Thread(target=self._hid_read_loop)
             self._thread.daemon = True
-            self._thread.setName('pySerial CP2110 reader thread for {}'.format(self._port))
+            self._thread.name = 'pySerial CP2110 reader thread for {}'.format(self._port)
             self._thread.start()
 
     def from_url(self, url):