diff --git a/mitogen/ssh.py b/mitogen/ssh.py
index 106dfd56..2bee15c8 100644
--- a/mitogen/ssh.py
+++ b/mitogen/ssh.py
@@ -100,7 +100,8 @@ def filter_debug(stream, it):
                 if b('\n') not in buf:
                     break
                 line, _, buf = buf.partition(b('\n'))
-                LOG.debug('%r: %s', stream, line.rstrip())
+                LOG.debug('%r: %s', stream,
+                          mitogen.core.to_text(line.rstrip()))
                 state = 'start_of_line'
             elif state == 'in_plain':
                 line, nl, buf = buf.partition(b('\n'))
diff --git a/tests/ssh_test.py b/tests/ssh_test.py
index 661ff5ed..abb25a58 100644
--- a/tests/ssh_test.py
+++ b/tests/ssh_test.py
@@ -44,6 +44,21 @@ class ConstructorTest(testlib.RouterMixin, testlib.TestCase):
 class SshTest(testlib.DockerMixin, testlib.TestCase):
     stream_class = mitogen.ssh.Stream
 
+    def test_debug_decoding(self):
+        # ensure filter_debug_logs() decodes the logged string.
+        capture = testlib.LogCapturer()
+        capture.start()
+        try:
+            context = self.docker_ssh(
+                username='mitogen__has_sudo',
+                password='has_sudo_password',
+                ssh_debug_level=3,
+            )
+        finally:
+            s = capture.stop()
+
+        self.assertTrue("'): debug1: Reading configuration data" in s)
+
     def test_stream_name(self):
         context = self.docker_ssh(
             username='mitogen__has_sudo',