diff --git a/lldb/packages/Python/lldbsuite/test/lldbtest.py b/lldb/packages/Python/lldbsuite/test/lldbtest.py
index 763e0619fed58..a4ff96e4158ce 100644
--- a/lldb/packages/Python/lldbsuite/test/lldbtest.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbtest.py
@@ -757,7 +757,7 @@ def getPlatformAvailablePorts(self):
     def setUpCommands(cls):
         commands = [
             # First of all, clear all settings to have clean state of global properties.
-            "settings clear -all",
+            "settings clear --all",
             # Disable Spotlight lookup. The testsuite creates
             # different binaries with the same UUID, because they only
             # differ in the debug info, which is not being hashed.