diff --git a/python/sglang/srt/server_args.py b/python/sglang/srt/server_args.py
index 317df60a6..99928f1b7 100644
--- a/python/sglang/srt/server_args.py
+++ b/python/sglang/srt/server_args.py
@@ -425,6 +425,12 @@ class ServerArgs:
                 "Overlap scheduler is disabled because of using "
                 "eagle speculative decoding."
             )
+            if self.enable_mixed_chunk:
+                self.enable_mixed_chunk = False
+                logger.warning(
+                    "Mixed chunked prefill is disabled because of using "
+                    "eagle speculative decoding."
+                )
 
             model_arch = get_model_arch(self)