diff --git a/test/parallel/test-writedouble.js b/test/parallel/test-writedouble.js
index b6a53842044340..cb1b0701531f06 100644
--- a/test/parallel/test-writedouble.js
+++ b/test/parallel/test-writedouble.js
@@ -189,8 +189,8 @@ function test(clazz) {
   // Darwin ia32 does the other kind of NaN.
   // Compiler bug.  No one really cares.
   assert(0x7F === buffer[15] || 0xFF === buffer[15]);
-  assert.ok(isNaN(buffer.readDoubleBE(0)));
-  assert.ok(isNaN(buffer.readDoubleLE(8)));
+  assert.ok(Number.isNaN(buffer.readDoubleBE(0)));
+  assert.ok(Number.isNaN(buffer.readDoubleLE(8)));
 }