diff --git a/src/transformers/models/glm4v/modeling_glm4v.py b/src/transformers/models/glm4v/modeling_glm4v.py
index fcd9f5f0d1a2..3bbfb57c8288 100644
--- a/src/transformers/models/glm4v/modeling_glm4v.py
+++ b/src/transformers/models/glm4v/modeling_glm4v.py
@@ -949,7 +949,7 @@ def forward(
 @auto_docstring
 class Glm4vModel(Glm4vPreTrainedModel):
     base_model_prefix = ""
-    _checkpoint_conversion_mapping = None
+    _checkpoint_conversion_mapping = {}
     config_class = Glm4vConfig
     _no_split_modules = ["Glm4vTextDecoderLayer", "Glm4vVisionBlock"]
 
@@ -1382,7 +1382,7 @@ class Glm4vCausalLMOutputWithPast(ModelOutput):
 
 
 class Glm4vForConditionalGeneration(Glm4vPreTrainedModel, GenerationMixin):
-    _checkpoint_conversion_mapping = None
+    _checkpoint_conversion_mapping = {}
     _tied_weights_keys = ["lm_head.weight"]
 
     def __init__(self, config):
diff --git a/src/transformers/models/glm4v/modular_glm4v.py b/src/transformers/models/glm4v/modular_glm4v.py
index 48cf2a7bb220..4b8ef1754b1b 100644
--- a/src/transformers/models/glm4v/modular_glm4v.py
+++ b/src/transformers/models/glm4v/modular_glm4v.py
@@ -1001,7 +1001,7 @@ def forward(
 
 
 class Glm4vModel(Qwen2_5_VLModel):
-    _checkpoint_conversion_mapping = None
+    _checkpoint_conversion_mapping = {}
     _no_split_modules = ["Glm4vTextDecoderLayer", "Glm4vVisionBlock"]
 
     def __init__(self, config):
@@ -1356,7 +1356,7 @@ class Glm4vCausalLMOutputWithPast(Qwen2_5_VLCausalLMOutputWithPast):
 
 
 class Glm4vForConditionalGeneration(Qwen2_5_VLForConditionalGeneration):
-    _checkpoint_conversion_mapping = None
+    _checkpoint_conversion_mapping = {}
 
     def forward(
         self,