diff --git a/src/libraries/System.Threading/tests/MutexTests.cs b/src/libraries/System.Threading/tests/MutexTests.cs
index a893662df15195..4af1d538bfabb7 100644
--- a/src/libraries/System.Threading/tests/MutexTests.cs
+++ b/src/libraries/System.Threading/tests/MutexTests.cs
@@ -348,7 +348,7 @@ public void AbandonExisting(
                             }
                             else
                             {
-                                Assert.True(m2Index < notAbandonedWaitIndex);
+                                Assert.True(!isNotAbandonedWaitObjectSignaled || m2Index < notAbandonedWaitIndex);
                                 Assert.Equal(m2Index, ame.MutexIndex);
                             }