diff --git a/Assets/VRM10/Editor/Components/SpringBone/VRM10SpringBoneJointEditor.cs b/Assets/VRM10/Editor/Components/SpringBone/VRM10SpringBoneJointEditor.cs
index 4a06dc63f..4e86a5153 100644
--- a/Assets/VRM10/Editor/Components/SpringBone/VRM10SpringBoneJointEditor.cs
+++ b/Assets/VRM10/Editor/Components/SpringBone/VRM10SpringBoneJointEditor.cs
@@ -149,7 +149,7 @@ namespace UniVRM10
                 return false;
             }
 
-            var (spring, i) = found.Value;
+            var (spring, i, _) = found.Value;
             m_showJoints = EditorGUILayout.Foldout(m_showJoints, $"Springs[{i}]({spring.Name})");
             int? jointIndex = default;
             // joints
@@ -198,22 +198,20 @@ namespace UniVRM10
             {
                 return;
             }
+
+            // joint(m_target) から、所属する spring を検索する。
             var found = m_root.SpringBone.FindJoint(m_target);
             if (!found.HasValue)
             {
                 return;
             }
+            // 所属 spring と joint(m_target) の index を得る
+            var (spring, i, j) = found.Value;
 
-            var (spring, i) = found.Value;
-            if (spring.Joints.Count > 0 && spring.Joints[0] != null)
-            {
-                var label = $"Springs[{i}]";
-                if (!string.IsNullOrEmpty(spring.Name))
-                {
-                    label = spring.Name;
-                }
-                Handles.Label(spring.Joints[0].transform.position, label);
-            }
+            var label = string.IsNullOrEmpty(spring.Name)
+                ? $"[{i}][{j}]{m_target.name}"
+                : $"[{i}]{spring.Name}[{j}]{m_target.name}";
+            Handles.Label(spring.Joints[j].transform.position, label);
         }
     }
 }
diff --git a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceSpringBone.cs b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceSpringBone.cs
index edc9b5397..f47a972c3 100644
--- a/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceSpringBone.cs
+++ b/Assets/VRM10/Runtime/Components/Vrm10Instance/Vrm10InstanceSpringBone.cs
@@ -77,13 +77,14 @@ namespace UniVRM10
         [SerializeField]
         public List<Spring> Springs = new List<Spring>();
 
-        public (Spring, int)? FindJoint(VRM10SpringBoneJoint joint)
+        public (Spring spring, int springIndex, int jointIndex)? FindJoint(VRM10SpringBoneJoint joint)
         {
             for (int i = 0; i < Springs.Count; ++i)
             {
-                if (Springs[i].Joints.Contains(joint))
+                var j = Springs[i].Joints.IndexOf(joint);
+                if (j >= 0)
                 {
-                    return (Springs[i], i);
+                    return new(Springs[i], i, j);
                 }
             }
             return default;