diff --git a/sentry_sdk/integrations/langchain.py b/sentry_sdk/integrations/langchain.py
index 11cf82c000..431fc46bec 100644
--- a/sentry_sdk/integrations/langchain.py
+++ b/sentry_sdk/integrations/langchain.py
@@ -138,7 +138,7 @@ def _create_span(self, run_id, parent_id, **kwargs):
 
         watched_span = None  # type: Optional[WatchedSpan]
         if parent_id:
-            parent_span = self.span_map[parent_id]  # type: Optional[WatchedSpan]
+            parent_span = self.span_map.get(parent_id)  # type: Optional[WatchedSpan]
             if parent_span:
                 watched_span = WatchedSpan(parent_span.span.start_child(**kwargs))
                 parent_span.children.append(watched_span)