diff --git a/NetworkPkg/IScsiDxe/IScsiConfig.c b/NetworkPkg/IScsiDxe/IScsiConfig.c
index 3631e72e34..16a90a6206 100644
--- a/NetworkPkg/IScsiDxe/IScsiConfig.c
+++ b/NetworkPkg/IScsiDxe/IScsiConfig.c
@@ -1111,7 +1111,7 @@ IScsiConfigUpdateAttempt (
   NET_LIST_FOR_EACH (Entry, &mPrivate->AttemptConfigs) {
     AttemptConfigData = NET_LIST_USER_STRUCT (Entry, ISCSI_ATTEMPT_CONFIG_NVDATA, Link);
 
-    AsciiStrToUnicodeStrS (AttemptConfigData->AttemptName, AttemptName, sizeof (AttemptName) / sizeof (AttemptName[0]));
+    AsciiStrToUnicodeStrS (AttemptConfigData->AttemptName, AttemptName, ARRAY_SIZE (AttemptName));
     UnicodeSPrint (mPrivate->PortString, (UINTN) 128, L"Attempt %s", AttemptName);
     AttemptConfigData->AttemptTitleToken = HiiSetString (
                                              mCallbackInfo->RegisteredHandle,
@@ -1240,7 +1240,7 @@ IScsiConfigDeleteAttempts (
       mPrivate->SinglePathCount--;
     }
 
-    AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, sizeof (MacString) / sizeof (MacString[0]));
+    AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, ARRAY_SIZE (MacString));
 
     UnicodeSPrint (
       mPrivate->PortString,
diff --git a/NetworkPkg/IScsiDxe/IScsiDriver.c b/NetworkPkg/IScsiDxe/IScsiDriver.c
index 279f1c0496..ac10fa26d1 100644
--- a/NetworkPkg/IScsiDxe/IScsiDriver.c
+++ b/NetworkPkg/IScsiDxe/IScsiDriver.c
@@ -673,7 +673,7 @@ IScsiStart (
     Session->ConfigData = AttemptConfigData;
     Session->AuthType   = AttemptConfigData->AuthenticationType;
 
-    AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, sizeof (MacString) / sizeof (MacString[0]));
+    AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, ARRAY_SIZE (MacString));
     UnicodeSPrint (
       mPrivate->PortString,
       (UINTN) ISCSI_NAME_IFR_MAX_SIZE,
diff --git a/NetworkPkg/IScsiDxe/IScsiMisc.c b/NetworkPkg/IScsiDxe/IScsiMisc.c
index 64bb2ade7b..11a80f2e10 100644
--- a/NetworkPkg/IScsiDxe/IScsiMisc.c
+++ b/NetworkPkg/IScsiDxe/IScsiMisc.c
@@ -1109,7 +1109,7 @@ IScsiGetConfigData (
           //
           // Refresh the state of this attempt to NVR.
           //
-          AsciiStrToUnicodeStrS (AttemptTmp->MacString, MacString, sizeof (MacString) / sizeof (MacString[0]));
+          AsciiStrToUnicodeStrS (AttemptTmp->MacString, MacString, ARRAY_SIZE (MacString));
           UnicodeSPrint (
             mPrivate->PortString,
             (UINTN) ISCSI_NAME_IFR_MAX_SIZE,
@@ -1148,7 +1148,7 @@ IScsiGetConfigData (
         //
         // Refresh the state of this attempt to NVR.
         //
-        AsciiStrToUnicodeStrS (AttemptTmp->MacString, MacString, sizeof (MacString) / sizeof (MacString[0]));
+        AsciiStrToUnicodeStrS (AttemptTmp->MacString, MacString, ARRAY_SIZE (MacString));
         UnicodeSPrint (
           mPrivate->PortString,
           (UINTN) ISCSI_NAME_IFR_MAX_SIZE,
@@ -1239,7 +1239,7 @@ IScsiGetConfigData (
       //
       // Refresh the state of this attempt to NVR.
       //
-      AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, sizeof (MacString) / sizeof (MacString[0]));
+      AsciiStrToUnicodeStrS (AttemptConfigData->MacString, MacString, ARRAY_SIZE (MacString));
       UnicodeSPrint (
         mPrivate->PortString,
         (UINTN) ISCSI_NAME_IFR_MAX_SIZE,