diff --git a/MdePkg/Library/UefiDevicePathLib/DevicePathFromText.c b/MdePkg/Library/UefiDevicePathLib/DevicePathFromText.c
index c66b77ba6c..35a73e83ff 100644
--- a/MdePkg/Library/UefiDevicePathLib/DevicePathFromText.c
+++ b/MdePkg/Library/UefiDevicePathLib/DevicePathFromText.c
@@ -2542,6 +2542,7 @@ DevPathFromTextiSCSI (
   CHAR16                      *ProtocolStr;
   CHAR8                       *AsciiStr;
   ISCSI_DEVICE_PATH_WITH_NAME *ISCSIDevPath;
+  UINT64                      Lun;
 
   NameStr           = GetNextParamStr (&TextDeviceNode);
   PortalGroupStr    = GetNextParamStr (&TextDeviceNode);
@@ -2560,7 +2561,8 @@ DevPathFromTextiSCSI (
   StrToAscii (NameStr, &AsciiStr);
 
   ISCSIDevPath->TargetPortalGroupTag = (UINT16) Strtoi (PortalGroupStr);
-  Strtoi64 (LunStr, &ISCSIDevPath->Lun);
+  Strtoi64 (LunStr, &Lun);
+  WriteUnaligned64 ((UINT64 *) &ISCSIDevPath->Lun, SwapBytes64 (Lun));
 
   Options = 0x0000;
   if (StrCmp (HeaderDigestStr, L"CRC32C") == 0) {