diff --git a/com.unity.ml-agents/CHANGELOG.md b/com.unity.ml-agents/CHANGELOG.md
index 8a028abaccc..af608358fd2 100755
--- a/com.unity.ml-agents/CHANGELOG.md
+++ b/com.unity.ml-agents/CHANGELOG.md
@@ -6,6 +6,11 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to
 [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+### Minor Changes
+#### com.unity.ml-agents (C#)
+- Make `BehaviorParametersEditor` create new sensors only when needed. (#6318, #6323)
+
 ## [4.1.0] - 2026-07-27
 ### Major Changes
 #### ml-agents / ml-agents-envs
diff --git a/com.unity.ml-agents/Editor/BehaviorParametersEditor.cs b/com.unity.ml-agents/Editor/BehaviorParametersEditor.cs
index 5518ac3db82..ae35e543c19 100644
--- a/com.unity.ml-agents/Editor/BehaviorParametersEditor.cs
+++ b/com.unity.ml-agents/Editor/BehaviorParametersEditor.cs
@@ -122,8 +122,12 @@ void DisplayFailedModelChecks()
             {
                 return;
             }
-            agent.sensors = new List<ISensor>();
-            agent.InitializeSensors();
+
+            if (!EditorApplication.isPlaying || agent.sensors == null)
+            {
+                agent.sensors = new List<ISensor>();
+                agent.InitializeSensors();
+            }
             var sensors = agent.sensors.ToArray();
 
             ActuatorComponent[] actuatorComponents;