diff --git a/setup.py b/setup.py
index 6951b501..2eb888a4 100644
--- a/setup.py
+++ b/setup.py
@@ -68,7 +68,7 @@ def is_macos_universal2():
         return False
 
     cflags = sysconfig.get_config_var('CFLAGS')
-    return '-arch x86_64' in cflags and '-arch x86_64' in cflags
+    return '-arch x86_64' in cflags and '-arch arm64' in cflags
 
 
 def determine_cross_compile_args():