diff --git a/tests/qemu-iotests/297 b/tests/qemu-iotests/297
index 345b617b34..1ee15dd866 100755
--- a/tests/qemu-iotests/297
+++ b/tests/qemu-iotests/297
@@ -46,7 +46,7 @@ def is_python_file(filename):
     if filename.endswith('.py'):
         return True
 
-    with open(filename) as f:
+    with open(filename, encoding='utf-8') as f:
         try:
             first_line = f.readline()
             return re.match('^#!.*python', first_line) is not None
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 11276f380a..d8c64d4c11 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -610,7 +610,7 @@ class VM(qtest.QEMUQtestMachine):
             return
         valgrind_filename =  f"{test_dir}/{self._popen.pid}.valgrind"
         if self.exitcode() == 99:
-            with open(valgrind_filename) as f:
+            with open(valgrind_filename, encoding='utf-8') as f:
                 print(f.read())
         else:
             os.remove(valgrind_filename)
@@ -1121,7 +1121,8 @@ def notrun(reason):
     # Each test in qemu-iotests has a number ("seq")
     seq = os.path.basename(sys.argv[0])
 
-    with open('%s/%s.notrun' % (output_dir, seq), 'w') as outfile:
+    with open('%s/%s.notrun' % (output_dir, seq), 'w', encoding='utf-8') \
+            as outfile:
         outfile.write(reason + '\n')
     logger.warning("%s not run: %s", seq, reason)
     sys.exit(0)
@@ -1135,7 +1136,8 @@ def case_notrun(reason):
     # Each test in qemu-iotests has a number ("seq")
     seq = os.path.basename(sys.argv[0])
 
-    with open('%s/%s.casenotrun' % (output_dir, seq), 'a') as outfile:
+    with open('%s/%s.casenotrun' % (output_dir, seq), 'a', encoding='utf-8') \
+            as outfile:
         outfile.write('    [case not run] ' + reason + '\n')
 
 def _verify_image_format(supported_fmts: Sequence[str] = (),