diff --git a/scripts/wan2.1/train.py b/scripts/wan2.1/train.py
index 4d3a827..c5aa7e6 100755
--- a/scripts/wan2.1/train.py
+++ b/scripts/wan2.1/train.py
@@ -773,8 +773,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/scripts/wan2.1/train_lora.py b/scripts/wan2.1/train_lora.py
index 50a1883..7c021dc 100755
--- a/scripts/wan2.1/train_lora.py
+++ b/scripts/wan2.1/train_lora.py
@@ -772,8 +772,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/scripts/wan2.1_fun/train.py b/scripts/wan2.1_fun/train.py
index 1863178..cf89f6e 100755
--- a/scripts/wan2.1_fun/train.py
+++ b/scripts/wan2.1_fun/train.py
@@ -743,8 +743,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/scripts/wan2.1_fun/train_control.py b/scripts/wan2.1_fun/train_control.py
index 23d01c6..ef471de 100755
--- a/scripts/wan2.1_fun/train_control.py
+++ b/scripts/wan2.1_fun/train_control.py
@@ -675,8 +675,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/scripts/wan2.1_fun/train_control_lora.py b/scripts/wan2.1_fun/train_control_lora.py
index 9a79d25..b36c39b 100755
--- a/scripts/wan2.1_fun/train_control_lora.py
+++ b/scripts/wan2.1_fun/train_control_lora.py
@@ -673,8 +673,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/scripts/wan2.1_fun/train_lora.py b/scripts/wan2.1_fun/train_lora.py
index e64e224..5d392fe 100755
--- a/scripts/wan2.1_fun/train_lora.py
+++ b/scripts/wan2.1_fun/train_lora.py
@@ -735,8 +735,12 @@ def main():
         zero_stage = 0
         if fsdp_plugin.sharding_strategy is ShardingStrategy.FULL_SHARD:
             fsdp_stage = 3
+        elif fsdp_plugin.sharding_strategy is None: # The fsdp_plugin.sharding_strategy is None in FSDP 2.
+            fsdp_stage = 3
         elif fsdp_plugin.sharding_strategy is ShardingStrategy.SHARD_GRAD_OP:
             fsdp_stage = 2
+        else:
+            fsdp_stage = 0
         print(f"Using FSDP stage: {fsdp_stage}")
 
         args.use_fsdp = True
diff --git a/videox_fun/models/wan_transformer3d.py b/videox_fun/models/wan_transformer3d.py
index 16bb296..ebb55ba 100755
--- a/videox_fun/models/wan_transformer3d.py
+++ b/videox_fun/models/wan_transformer3d.py
@@ -2,6 +2,7 @@
 # Copyright 2024-2025 The Alibaba Wan Team Authors. All rights reserved.
 
 import glob
+import importlib.metadata
 import json
 import math
 import os
@@ -17,6 +18,7 @@ from diffusers.configuration_utils import ConfigMixin, register_to_config
 from diffusers.loaders.single_file_model import FromOriginalModelMixin
 from diffusers.models.modeling_utils import ModelMixin
 from diffusers.utils import is_torch_version, logging
+from packaging import version
 from torch import nn
 
 from ..dist import (get_sequence_parallel_rank,
@@ -60,6 +62,13 @@ except:
         sageattn = None
         SAGE_ATTENTION_AVAILABLE = False
 
+try:
+    diffusers_version = importlib.metadata.version("diffusers")
+except importlib.metadata.PackageNotFoundError:
+    diffusers_version = "0.0.0"
+
+USE_NEW_SIGNATURE = version.parse(diffusers_version) >= version.parse("0.33.1")
+
 def flash_attention(
     q,
     k,
@@ -843,7 +852,14 @@ class WanTransformer3DModel(ModelMixin, ConfigMixin, FromOriginalModelMixin):
         self.gradient_checkpointing = False
         self.sp_world_size = 1
         self.sp_world_rank = 0
-    
+
+        if USE_NEW_SIGNATURE:
+            def _set_gradient_checkpointing(self, enable=False, gradient_checkpointing_func=None):
+                self.gradient_checkpointing = enable
+        else:
+            def _set_gradient_checkpointing(self, module, value=False):
+                self.gradient_checkpointing = value
+
     def enable_teacache(
         self,
         coefficients,
@@ -908,9 +924,6 @@ class WanTransformer3DModel(ModelMixin, ConfigMixin, FromOriginalModelMixin):
             block.self_attn.forward = types.MethodType(
                 usp_attn_forward, block.self_attn)
 
-    def _set_gradient_checkpointing(self, module, value=False):
-        self.gradient_checkpointing = value
-
     @cfg_skip()
     def forward(
         self,