diff --git a/python/sglang/srt/function_call/deepseekv31_detector.py b/python/sglang/srt/function_call/deepseekv31_detector.py
index cab924544..f9891d96f 100644
--- a/python/sglang/srt/function_call/deepseekv31_detector.py
+++ b/python/sglang/srt/function_call/deepseekv31_detector.py
@@ -114,13 +114,14 @@ class DeepSeekV31Detector(BaseFormatDetector):
         calls: list[ToolCallItem] = []
         try:
             partial_match = re.search(
-                pattern=r"<｜tool▁call▁begin｜>(.*)<｜tool▁sep｜>(.*)<｜tool▁call▁end｜>",
+                pattern=r"<｜tool▁call▁begin｜>(.*)<｜tool▁sep｜>(.*?)(<｜tool▁call▁end｜>|$)",
                 string=current_text,
                 flags=re.DOTALL,
             )
             if partial_match:
                 func_name = partial_match.group(1).strip()
                 func_args_raw = partial_match.group(2).strip()
+                is_tool_end = partial_match.group(3)
 
                 # Initialize state if this is the first tool call
                 if self.current_tool_id == -1:
@@ -179,15 +180,9 @@ class DeepSeekV31Detector(BaseFormatDetector):
                             pass
 
                         # Find the end of the current tool call and remove only that part from buffer
-                        tool_call_end_pattern = (
-                            r"<｜tool▁call▁begin｜>.*?<｜tool▁call▁end｜>"
-                        )
-                        match = re.search(
-                            tool_call_end_pattern, current_text, re.DOTALL
-                        )
-                        if match:
+                        if is_tool_end:
                             # Remove the completed tool call from buffer, keep any remaining content
-                            self._buffer = current_text[match.end() :]
+                            self._buffer = current_text[partial_match.end(3) :]
                         else:
                             self._buffer = ""