diff --git a/src/main/resources/lang/ja-JP/strings.yml b/src/main/resources/lang/ja-JP/strings.yml
index 35af3e14e..caac0e532 100644
--- a/src/main/resources/lang/ja-JP/strings.yml
+++ b/src/main/resources/lang/ja-JP/strings.yml
@@ -91,12 +91,12 @@ questClearItem: "アイテムのクリア"
 questGUICleared: "クエストGUI Itemの表示がクリアされました"
 questDeleted: "クエストを削除! クエストとイベントがリロードされました"
 questEditorNameExists: "その名前は既に使われています"
-questEditorBeingEdited: "Someone is creating/editing a Quest with that name!"
-questEditorInvalidQuestName: "Name may not contain periods or commas!"
-questEditorInvalidEventName: "is not a valid event name!"
-questEditorInvalidNPC: "No NPC exists with that id!"
-questEditorNoStartBlockSelected: "You must select a block first."
-questEditorPositiveAmount: "Amount must be a positive number."
+questEditorBeingEdited: "その名前のクエストを誰かが 作成/編集 中です"
+questEditorInvalidQuestName: "名前にはピリオド(.) やカンマ(,) を含めることはできません!"
+questEditorInvalidEventName: "そのイベント名は有効ではありません!"
+questEditorInvalidNPC: "そのIDを持つNPCは存在しません"
+questEditorNoStartBlockSelected: "ブロックを先に選択してください"
+questEditorPositiveAmount: "0より大きいかずでなければなりません"
 questEditorQuestAsRequirement1: "The following Quests have"
 questEditorQuestAsRequirement2: "as a requirement:"
 questEditorQuestAsRequirement3: "You must modify these Quests so that they do not use it before deleting it."