diff --git a/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.c b/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.c
index 9f5be15ce6..dfc79a067b 100644
--- a/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.c
+++ b/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.c
@@ -30,22 +30,22 @@
 EFI_STATUS
 PxeBcFlushStationIp (
   PXEBC_PRIVATE_DATA       *Private,
-  EFI_IP_ADDRESS           *StationIp,
+  EFI_IP_ADDRESS           *StationIp,     OPTIONAL
   EFI_IP_ADDRESS           *SubnetMask     OPTIONAL
   )
 {
   EFI_PXE_BASE_CODE_MODE   *Mode;
   EFI_STATUS               Status;
 
-  ASSERT (StationIp != NULL);
-
   Mode   = Private->PxeBc.Mode;
   Status = EFI_SUCCESS;
 
   if (Mode->UsingIpv6) {
 
-    CopyMem (&Private->Udp6CfgData.StationAddress, StationIp, sizeof (EFI_IPv6_ADDRESS));
-    CopyMem (&Private->Ip6CfgData.StationAddress, StationIp, sizeof (EFI_IPv6_ADDRESS));
+    if (StationIp != NULL) {
+      CopyMem (&Private->Udp6CfgData.StationAddress, StationIp, sizeof (EFI_IPv6_ADDRESS));
+      CopyMem (&Private->Ip6CfgData.StationAddress, StationIp, sizeof (EFI_IPv6_ADDRESS));
+    }
 
     //
     // Reconfigure the Ip6 instance to capture background ICMP6 packets with new station Ip address.
@@ -60,11 +60,15 @@ PxeBcFlushStationIp (
 
     Status = Private->Ip6->Receive (Private->Ip6, &Private->Icmp6Token);
   } else {
-    ASSERT (SubnetMask != NULL);
-    CopyMem (&Private->Udp4CfgData.StationAddress, StationIp, sizeof (EFI_IPv4_ADDRESS));
-    CopyMem (&Private->Udp4CfgData.SubnetMask, SubnetMask, sizeof (EFI_IPv4_ADDRESS));
-    CopyMem (&Private->Ip4CfgData.StationAddress, StationIp, sizeof (EFI_IPv4_ADDRESS));
-    CopyMem (&Private->Ip4CfgData.SubnetMask, SubnetMask, sizeof (EFI_IPv4_ADDRESS));
+    if (StationIp != NULL) {
+      CopyMem (&Private->Udp4CfgData.StationAddress, StationIp, sizeof (EFI_IPv4_ADDRESS));
+      CopyMem (&Private->Ip4CfgData.StationAddress, StationIp, sizeof (EFI_IPv4_ADDRESS));
+    }
+    
+    if (SubnetMask != NULL) {
+      CopyMem (&Private->Udp4CfgData.SubnetMask, SubnetMask, sizeof (EFI_IPv4_ADDRESS));
+      CopyMem (&Private->Ip4CfgData.SubnetMask, SubnetMask, sizeof (EFI_IPv4_ADDRESS));
+    }
 
     //
     // Reconfigure the Ip4 instance to capture background ICMP packets with new station Ip address.
diff --git a/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.h b/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.h
index b8519ae8c8..17bee5c279 100644
--- a/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.h
+++ b/NetworkPkg/UefiPxeBcDxe/PxeBcSupport.h
@@ -1,7 +1,7 @@
 /** @file
   Support functions declaration for UefiPxeBc Driver.
 
-  Copyright (c) 2007 - 2016, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2007 - 2017, Intel Corporation. All rights reserved.<BR>
 
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
@@ -40,7 +40,7 @@
 EFI_STATUS
 PxeBcFlushStationIp (
   PXEBC_PRIVATE_DATA       *Private,
-  EFI_IP_ADDRESS           *StationIp,
+  EFI_IP_ADDRESS           *StationIp,     OPTIONAL
   EFI_IP_ADDRESS           *SubnetMask     OPTIONAL
   );