diff --git a/MdePkg/Include/Protocol/DtFixup.h b/MdePkg/Include/Protocol/DtFixup.h
new file mode 100644
index 0000000000..0f6f3849f9
--- /dev/null
+++ b/MdePkg/Include/Protocol/DtFixup.h
@@ -0,0 +1,42 @@
+/** @file
+  Device Tree Fixup Protocol.
+
+  Modifies a device tree in memory to align it with the firmware's view of
+  the platform.
+
+  Specification:
+  https://github.com/U-Boot-EFI/EFI_DT_FIXUP_PROTOCOL
+
+  Copyright (c) 2025, Heinrich Schuchardt.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#pragma once
+
+#include <Uefi/UefiBaseType.h>
+
+//
+// {60ed6ba9-dfef-4799-ac7b-75e0f833456c}
+//
+#define DT_FIXUP_PROTOCOL_GUID \
+  { 0x60ed6ba9, 0xdfef, 0x4799, { 0xac, 0x7b, 0x75, 0xe0, 0xf8, 0x33, 0x45, 0x6c } }
+
+#define DT_FIXUP_PROTOCOL_REVISION  0x00010000
+
+typedef struct _DT_FIXUP_PROTOCOL DT_FIXUP_PROTOCOL;
+
+typedef
+EFI_STATUS
+(EFIAPI *DT_FIXUP)(
+  IN DT_FIXUP_PROTOCOL *This,
+  IN OUT VOID          *Fdt,
+  IN OUT UINTN         *BufferSize
+  );
+
+struct _DT_FIXUP_PROTOCOL {
+  UINT64      Revision;
+  DT_FIXUP    Fixup;
+};
+
+extern EFI_GUID  gDtFixupProtocolGuid;
diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index a0b18916a9..92e6f98a72 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -1159,6 +1159,9 @@
   ## Include/Protocol/CcMeasurement.h
   gEfiCcMeasurementProtocolGuid  = { 0x96751a3d, 0x72f4, 0x41a6, { 0xa7, 0x94, 0xed, 0x5d, 0x0e, 0x67, 0xae, 0x6b }}
 
+  ## Include/Protocol/DtFixup.h
+  gDtFixupProtocolGuid           = { 0x60ed6ba9, 0xdfef, 0x4799, { 0xac, 0x7b, 0x75, 0xe0, 0xf8, 0x33, 0x45, 0x6c }}
+
   #
   # Protocols defined in PI1.0.
   #