diff --git a/crates/oxc_formatter/src/parentheses/expression.rs b/crates/oxc_formatter/src/parentheses/expression.rs
index 4d3c9af9f6713..7c7a01dca2fb1 100644
--- a/crates/oxc_formatter/src/parentheses/expression.rs
+++ b/crates/oxc_formatter/src/parentheses/expression.rs
@@ -416,6 +416,7 @@ impl<'a> NeedsParentheses<'a> for AstNode<'a, PrivateInExpression<'a>> {
         }
 
         is_class_extends(self.span, self.parent)
+            || matches!(self.parent, AstNodes::UnaryExpression(_))
     }
 }
 
diff --git a/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js b/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js
new file mode 100644
index 0000000000000..838381a09f102
--- /dev/null
+++ b/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js
@@ -0,0 +1,8 @@
+class F {
+  #target = null
+  next () {
+    !(#target in this);
+    -(#target in this);
+    +(#target in this);
+  }
+}
diff --git a/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js.snap b/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js.snap
new file mode 100644
index 0000000000000..e4b2129ccc4be
--- /dev/null
+++ b/crates/oxc_formatter/tests/fixtures/js/private-fields/parenthesis.js.snap
@@ -0,0 +1,24 @@
+---
+source: crates/oxc_formatter/tests/fixtures/mod.rs
+---
+==================== Input ====================
+class F {
+  #target = null
+  next () {
+    !(#target in this);
+    -(#target in this);
+    +(#target in this);
+  }
+}
+
+==================== Output ====================
+class F {
+  #target = null;
+  next() {
+    !(#target in this);
+    -(#target in this);
+    +(#target in this);
+  }
+}
+
+===================== End =====================