diff --git a/perception/radar_fusion_to_detected_object/src/radar_fusion_to_detected_object.cpp b/perception/radar_fusion_to_detected_object/src/radar_fusion_to_detected_object.cpp
index 839a606c0e307..75684d51039fd 100644
--- a/perception/radar_fusion_to_detected_object/src/radar_fusion_to_detected_object.cpp
+++ b/perception/radar_fusion_to_detected_object/src/radar_fusion_to_detected_object.cpp
@@ -296,7 +296,7 @@ TwistWithCovariance RadarFusionToDetectedObject::estimateTwist(
 bool RadarFusionToDetectedObject::isQualified(
   const DetectedObject & object, std::shared_ptr<std::vector<RadarInput>> & radars)
 {
-  if (object.classification[0].probability > param_.threshold_probability) {
+  if (object.existence_probability > param_.threshold_probability) {
     return true;
   } else {
     if (!radars || !(*radars).empty()) {