diff --git a/lib/yaml/emitter.py b/lib/yaml/emitter.py
index a664d0111..79c13d925 100644
--- a/lib/yaml/emitter.py
+++ b/lib/yaml/emitter.py
@@ -571,8 +571,8 @@ def prepare_tag_prefix(self, prefix):
                     chunks.append(prefix[start:end])
                 start = end = end+1
                 data = ch.encode('utf-8')
-                for ch in data:
-                    chunks.append('%%%02X' % ord(ch))
+                for byte in data:
+                    chunks.append('%%%02X' % byte)
         if start < end:
             chunks.append(prefix[start:end])
         return ''.join(chunks)
diff --git a/tests/test_emit.py b/tests/test_emit.py
new file mode 100644
index 000000000..fe3016989
--- /dev/null
+++ b/tests/test_emit.py
@@ -0,0 +1,12 @@
+import io
+
+import yaml
+
+
+def test_emit_tag_directive_with_percent_encoded_prefix_from_bytes():
+    events = list(yaml.parse(io.BytesIO(b"%TAG ! tag:%002:\n---")))
+
+    output = yaml.emit(events)
+
+    assert output == "%TAG ! tag:%002:\n---\n...\n"
+    assert list(yaml.parse(output))[1].tags == events[1].tags