diff --git a/vllm/config.py b/vllm/config.py
index 60a32fb182dbb..e8475efcb56e1 100644
--- a/vllm/config.py
+++ b/vllm/config.py
@@ -701,7 +701,7 @@ def get_num_layers_by_block_type(
 
         if self.is_attention_free and attn_block_type:
             return 0
-        if is_full_attn_model and attn_block_type:
+        if is_full_attn_model and not attn_block_type:
             return 0
 
         start, end = self.get_layers_start_end_indices(parallel_config)