diff --git a/Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs b/Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs
index 0614e9dcf..30969bba7 100644
--- a/Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs
+++ b/Assets/VRM/UniVRM/Editor/Format/VRMExporterWizard.cs
@@ -700,6 +700,7 @@ namespace VRM
 
             m_validations.Clear();
             m_validations.AddRange(Validate());
+            m_validations.AddRange(VRMSpringBoneValidator.Validate(ExportRoot));
             var hasError = m_validations.Any(x => !x.CanExport);
             m_IsValid = !hasError && !MetaHasError;
 
diff --git a/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs b/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs
new file mode 100644
index 000000000..d4abef440
--- /dev/null
+++ b/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs
@@ -0,0 +1,70 @@
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+
+namespace VRM
+{
+    static class VRMSpringBoneValidator
+    {
+        // https://github.com/vrm-c/UniVRM/issues/474
+        public static IEnumerable<Validation> Validate(GameObject root)
+        {
+            if (root == null)
+            {
+                yield break;
+            }
+
+            Dictionary<Transform, List<VRMSpringBone>> rootMap = new Dictionary<Transform, List<VRMSpringBone>>();
+
+            foreach (var sb in root.GetComponentsInChildren<VRMSpringBone>())
+            {
+                foreach (var springRoot in sb.RootBones)
+                {
+                    if (!rootMap.TryGetValue(springRoot, out List<VRMSpringBone> list))
+                    {
+                        list = new List<VRMSpringBone>();
+                        rootMap.Add(springRoot, list);
+                    }
+                    list.Add(sb);
+                }
+            }
+
+            foreach (var kv in rootMap)
+            {
+                if (kv.Value.Count > 1)
+                {
+                    // * GameObjectが複数回ルートとして指定されてる(SpringBoneが同じでも別でも)
+                    var list = string.Join(", ", kv.Value.Select(x => string.IsNullOrEmpty(x.m_comment) ? x.name : x.m_comment));
+                    yield return Validation.Warning($"{kv.Key} found multiple. {list}");
+                }
+
+                var rootInRootMap = new Dictionary<Transform, List<Transform>>();
+                foreach (var child in kv.Key.GetComponentsInChildren<Transform>())
+                {
+                    // * Rootから子をだどって、別のRootが現れる
+                    if (child == kv.Key)
+                    {
+                        continue;
+                    }
+
+                    if (!rootMap.ContainsKey(child))
+                    {
+                        continue;
+                    }
+
+                    if (!rootInRootMap.TryGetValue(kv.Key, out List<Transform> rootInRoot))
+                    {
+                        rootInRoot = new List<Transform>();
+                        rootInRootMap.Add(kv.Key, rootInRoot);
+                    }
+                    rootInRoot.Add(child);
+                }
+                foreach (var rootList in rootInRootMap)
+                {
+                    var list = string.Join(", ", rootList.Value.Select(x => x.name));
+                    yield return Validation.Warning($"{rootList.Key} hierarchy contains other root: {list}");
+                }
+            }
+        }
+    }
+}
diff --git a/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs.meta b/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs.meta
new file mode 100644
index 000000000..1a9e37b00
--- /dev/null
+++ b/Assets/VRM/UniVRM/Editor/SpringBone/VRMSpringBoneValidator.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: dc588ccd280c0e2429d1d3cc3db5d950
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: