diff --git a/airflow-core/src/airflow/models/mappedoperator.py b/airflow-core/src/airflow/models/mappedoperator.py
index bc598ef0469a8..205e8da16dd8d 100644
--- a/airflow-core/src/airflow/models/mappedoperator.py
+++ b/airflow-core/src/airflow/models/mappedoperator.py
@@ -62,7 +62,7 @@ def expand_start_from_trigger(self, *, context: Context, session: Session) -> bo
 
         :meta private:
         """
-        if self.partial_kwargs.get("start_from_trigger", self.start_from_trigger):
+        if not self.partial_kwargs.get("start_from_trigger", self.start_from_trigger):
             log.warning(
                 "Starting a mapped task from triggerer is currently unsupported",
                 task_id=self.task_id,