diff --git a/src/llmtuner/webui/runner.py b/src/llmtuner/webui/runner.py
index 5793001a..9e13a651 100644
--- a/src/llmtuner/webui/runner.py
+++ b/src/llmtuner/webui/runner.py
@@ -112,7 +112,7 @@ class Runner:
             overwrite_cache=True,
             checkpoint_dir=checkpoint_dir,
             finetuning_type=finetuning_type,
-            quantization_bit=int(quantization_bit) if quantization_bit & quantization_bit != "None" else None,
+            quantization_bit=int(quantization_bit) if quantization_bit and quantization_bit != "None" else None,
             template=template,
             system_prompt=system_prompt,
             dataset_dir=dataset_dir,
@@ -196,7 +196,7 @@ class Runner:
             predict_with_generate=True,
             checkpoint_dir=checkpoint_dir,
             finetuning_type=finetuning_type,
-            quantization_bit=int(quantization_bit) if quantization_bit & quantization_bit != "None" else None,
+            quantization_bit=int(quantization_bit) if quantization_bit and quantization_bit != "None" else None,
             template=template,
             system_prompt=system_prompt,
             dataset_dir=dataset_dir,