diff --git a/src/libraries/System.IO.Ports/src/System/IO/Ports/SerialStream.Windows.cs b/src/libraries/System.IO.Ports/src/System/IO/Ports/SerialStream.Windows.cs
index fa79f2a9c1e0ea..781024d5518350 100644
--- a/src/libraries/System.IO.Ports/src/System/IO/Ports/SerialStream.Windows.cs
+++ b/src/libraries/System.IO.Ports/src/System/IO/Ports/SerialStream.Windows.cs
@@ -769,7 +769,7 @@ protected override void Dispose(bool disposing)
                     {
                         lock (this)
                         {
-                            _handle.Close();
+                            _handle?.Close();
                             _handle = null;
                             _threadPoolBinding.Dispose();
                         }