diff --git a/packages/mui-joy/src/Select/Select.tsx b/packages/mui-joy/src/Select/Select.tsx
index 442e532cc7e215..82e7a2e6ee2c05 100644
--- a/packages/mui-joy/src/Select/Select.tsx
+++ b/packages/mui-joy/src/Select/Select.tsx
@@ -178,7 +178,7 @@ const SelectButton = styled('button', {
   alignItems: 'center',
   flex: 1,
   cursor: 'pointer',
-  ...(!ownerState.value && {
+  ...((ownerState.value === null || ownerState.value === undefined) && {
     opacity: 'var(--Select-placeholderOpacity)',
   }),
 }));