diff --git a/harness/typeCoercion.js b/harness/typeCoercion.js
index 76d366d7628c41faba87df049b4eaa91bfdb0143..3950d4b2cc79e7a46c33066ae77cd95109c486b5 100644
--- a/harness/typeCoercion.js
+++ b/harness/typeCoercion.js
@@ -330,8 +330,8 @@ function testCoercibleToBigIntZero(test) {
     testPrimitiveWrappers(value, "number", test);
   }
 
-  testCoercibleToBigIntFromBigInt(0n, test);
-  testPrimitiveValue(-0n);
+  testCoercibleToBigIntFromBigInt(BigInt(0), test);
+  testPrimitiveValue(-BigInt(0));
   testPrimitiveValue("-0");
   testPrimitiveValue(false);
   testPrimitiveValue("");
@@ -351,7 +351,7 @@ function testCoercibleToBigIntOne(test) {
     testPrimitiveWrappers(value, "number", test);
   }
 
-  testCoercibleToBigIntFromBigInt(1n, test);
+  testCoercibleToBigIntFromBigInt(BigInt(1), test);
   testPrimitiveValue(true);
 
   // toString() returns "1"