diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 5d561ff484..cc397185f7 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -1043,6 +1043,14 @@
   # @Prompt Maximum authenticated variable size.
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize|0x00|UINT32|0x30000009
 
+  ## The maximum size of a single non-authenticated volatile variable.
+  # The default value is 0 for compatibility: in that case, the maximum
+  # non-authenticated volatile variable size remains specified by
+  # PcdMaxVariableSize. Only the MdeModulePkg/Universal/Variable/RuntimeDxe
+  # driver supports this PCD.
+  # @Prompt Maximum non-authenticated volatile variable size.
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVolatileVariableSize|0x00|UINT32|0x3000000a
+
   ## The maximum size of single hardware error record variable.<BR><BR>
   # In IA32/X64 platforms, this value should be larger than 1KB.<BR>
   # In IA64 platforms, this value should be larger than 128KB.<BR>
diff --git a/MdeModulePkg/MdeModulePkg.uni b/MdeModulePkg/MdeModulePkg.uni
index f3fa616438..080b8a62c0 100644
--- a/MdeModulePkg/MdeModulePkg.uni
+++ b/MdeModulePkg/MdeModulePkg.uni
@@ -94,6 +94,14 @@
 #string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdMaxAuthVariableSize_HELP  #language en-US "The maximum size of a single authenticated variable."
                                                                                         "The value is 0 as default for compatibility that maximum authenticated variable size is specified by PcdMaxVariableSize."
 
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdMaxVolatileVariableSize_PROMPT  #language en-US "The maximum size of a single non-authenticated volatile variable."
+
+#string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdMaxVolatileVariableSize_HELP  #language en-US "The maximum size of a single non-authenticated volatile variable.<BR><BR>\n"
+                                                                                            "The default value is 0 for compatibility: in that case, the maximum "
+                                                                                            "non-authenticated volatile variable size remains specified by "
+                                                                                            "PcdMaxVariableSize.<BR>\n"
+                                                                                            "Only the MdeModulePkg/Universal/Variable/RuntimeDxe driver supports this PCD.<BR>"
+
 #string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdMaxHardwareErrorVariableSize_PROMPT  #language en-US "Maximum HwErr variable size"
 
 #string STR_gEfiMdeModulePkgTokenSpaceGuid_PcdMaxHardwareErrorVariableSize_HELP  #language en-US "The maximum size of single hardware error record variable.<BR><BR>\n"
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index c11842b5c3..6caf603b3d 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -2345,12 +2345,14 @@ UpdateVariable (
         CopyMem (BufferForMerge, (UINT8 *) ((UINTN) CacheVariable->CurrPtr + DataOffset), DataSizeOfVariable (CacheVariable->CurrPtr));
 
         //
-        // Set Max Common/Auth Variable Data Size as default MaxDataSize.
+        // Set Max Auth/Non-Volatile/Volatile Variable Data Size as default MaxDataSize.
         //
         if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
           MaxDataSize = mVariableModuleGlobal->MaxAuthVariableSize - DataOffset;
-        } else {
+        } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
           MaxDataSize = mVariableModuleGlobal->MaxVariableSize - DataOffset;
+        } else {
+          MaxDataSize = mVariableModuleGlobal->MaxVolatileVariableSize - DataOffset;
         }
 
         //
@@ -3218,16 +3220,20 @@ VariableServiceSetVariable (
   } else {
     //
     //  The size of the VariableName, including the Unicode Null in bytes plus
-    //  the DataSize is limited to maximum size of Max(Auth)VariableSize bytes.
+    //  the DataSize is limited to maximum size of Max(Auth|Volatile)VariableSize bytes.
     //
     if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
       if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxAuthVariableSize - GetVariableHeaderSize ()) {
         return EFI_INVALID_PARAMETER;
       }
-    } else {
+    } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
       if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxVariableSize - GetVariableHeaderSize ()) {
         return EFI_INVALID_PARAMETER;
       }
+    } else {
+      if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxVolatileVariableSize - GetVariableHeaderSize ()) {
+        return EFI_INVALID_PARAMETER;
+      }
     }
   }
 
@@ -3399,12 +3405,14 @@ VariableServiceQueryVariableInfoInternal (
     }
 
     //
-    // Let *MaximumVariableSize be Max(Auth)VariableSize with the exception of the variable header size.
+    // Let *MaximumVariableSize be Max(Auth|Volatile)VariableSize with the exception of the variable header size.
     //
     if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
       *MaximumVariableSize = mVariableModuleGlobal->MaxAuthVariableSize - GetVariableHeaderSize ();
-    } else {
+    } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
       *MaximumVariableSize = mVariableModuleGlobal->MaxVariableSize - GetVariableHeaderSize ();
+    } else {
+      *MaximumVariableSize = mVariableModuleGlobal->MaxVolatileVariableSize - GetVariableHeaderSize ();
     }
   }
 
@@ -3657,6 +3665,30 @@ GetNonVolatileMaxVariableSize (
   }
 }
 
+/**
+  Get maximum variable size, covering both non-volatile and volatile variables.
+
+  @return Maximum variable size.
+
+**/
+UINTN
+GetMaxVariableSize (
+  VOID
+  )
+{
+  UINTN MaxVariableSize;
+
+  MaxVariableSize = GetNonVolatileMaxVariableSize();
+  //
+  // The condition below fails implicitly if PcdMaxVolatileVariableSize equals
+  // the default zero value.
+  //
+  if (MaxVariableSize < PcdGet32 (PcdMaxVolatileVariableSize)) {
+    MaxVariableSize = PcdGet32 (PcdMaxVolatileVariableSize);
+  }
+  return MaxVariableSize;
+}
+
 /**
   Init non-volatile variable store.
 
@@ -4225,10 +4257,14 @@ VariableCommonInitialize (
     }
   }
 
+  mVariableModuleGlobal->MaxVolatileVariableSize = ((PcdGet32 (PcdMaxVolatileVariableSize) != 0) ?
+                                                    PcdGet32 (PcdMaxVolatileVariableSize) :
+                                                    mVariableModuleGlobal->MaxVariableSize
+                                                    );
   //
   // Allocate memory for volatile variable store, note that there is a scratch space to store scratch data.
   //
-  ScratchSize = GetNonVolatileMaxVariableSize ();
+  ScratchSize = GetMaxVariableSize ();
   mVariableModuleGlobal->ScratchBufferSize = ScratchSize;
   VolatileVariableStore = AllocateRuntimePool (PcdGet32 (PcdVariableStoreSize) + ScratchSize);
   if (VolatileVariableStore == NULL) {
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
index b35e8ab912..938eb5de61 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.h
@@ -101,6 +101,7 @@ typedef struct {
   UINTN           HwErrVariableTotalSize;
   UINTN           MaxVariableSize;
   UINTN           MaxAuthVariableSize;
+  UINTN           MaxVolatileVariableSize;
   UINTN           ScratchBufferSize;
   CHAR8           *PlatformLangCodes;
   CHAR8           *LangCodes;
@@ -460,6 +461,17 @@ GetNonVolatileMaxVariableSize (
   VOID
   );
 
+/**
+  Get maximum variable size, covering both non-volatile and volatile variables.
+
+  @return Maximum variable size.
+
+**/
+UINTN
+GetMaxVariableSize (
+  VOID
+  );
+
 /**
   Initializes variable write service after FVB was ready.
 
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
index e840fc9bff..2d0a172ece 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf
@@ -123,6 +123,7 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64    ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize                 ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize             ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVolatileVariableSize         ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize    ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize               ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdHwErrStorageSize                ## CONSUMES
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
index 8d73b6edee..e495d971a0 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
@@ -955,7 +955,7 @@ VariableServiceInitialize (
                     );
   ASSERT_EFI_ERROR (Status);
 
-  mVariableBufferPayloadSize = GetNonVolatileMaxVariableSize () +
+  mVariableBufferPayloadSize = GetMaxVariableSize () +
                                OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) - GetVariableHeaderSize ();
 
   Status = gSmst->SmmAllocatePool (
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
index 69966f0d37..dbb0674a46 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf
@@ -125,6 +125,7 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64     ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVariableSize                  ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxAuthVariableSize              ## CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdMaxVolatileVariableSize          ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxHardwareErrorVariableSize     ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize                ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdHwErrStorageSize                 ## CONSUMES