diff --git a/florence2_models/configuration_florence2.py b/florence2_models/configuration_florence2.py
index 622f749..3b29888 100644
--- a/florence2_models/configuration_florence2.py
+++ b/florence2_models/configuration_florence2.py
@@ -262,7 +262,7 @@ class Florence2LanguageConfig(PretrainedConfig):
         )
 
         # ensure backward compatibility for BART CNN models
-        if self.forced_bos_token_id is None and kwargs.get("force_bos_token_to_be_generated", False):
+        if getattr(self, 'forced_bos_token_id', None) is None and kwargs.get("force_bos_token_to_be_generated", False):
             self.forced_bos_token_id = self.bos_token_id
             warnings.warn(
                 f"Please make sure the config includes `forced_bos_token_id={self.bos_token_id}` in future versions. "
diff --git a/py/florence2_ultra.py b/py/florence2_ultra.py
index a6374b3..ffcd8eb 100644
--- a/py/florence2_ultra.py
+++ b/py/florence2_ultra.py
@@ -43,6 +43,19 @@ def fixed_get_imports(filename) -> list[str]:
         pass
     return imports
 
+def _patch_florence2_config_compat():
+    """Patch PretrainedConfig for transformers 5.x compatibility.
+
+    In transformers 5.x, generation-related attributes like forced_bos_token_id
+    were moved to GenerationConfig and are no longer set by PretrainedConfig.
+    Florence2's custom config code accesses self.forced_bos_token_id, which
+    raises AttributeError without this patch.
+    """
+    from transformers.configuration_utils import PretrainedConfig
+    for attr in ('forced_bos_token_id', 'forced_eos_token_id'):
+        if not hasattr(PretrainedConfig, attr):
+            setattr(PretrainedConfig, attr, None)
+
 def load_model(version):
     florence_path = os.path.join(folder_paths.models_dir, "florence2")
     os.makedirs(florence_path, exist_ok=True)
@@ -56,6 +69,8 @@ def load_model(version):
         from huggingface_hub import snapshot_download
         snapshot_download(repo_id=repo_id, local_dir=model_path, ignore_patterns=["*.md", "*.txt"])
 
+    _patch_florence2_config_compat()
+
     try:
         with patch("transformers.dynamic_module_utils.get_imports", fixed_get_imports):
             # model = AutoModelForCausalLM.from_pretrained(model_path, trust_remote_code=True)