diff --git a/source/src/main/java/one/nem/lacerta/source/database/entity/CombineDocumentEntity.java b/source/src/main/java/one/nem/lacerta/source/database/entity/CombineDocumentEntity.java
deleted file mode 100644
index e1b0234d..00000000
--- a/source/src/main/java/one/nem/lacerta/source/database/entity/CombineDocumentEntity.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package one.nem.lacerta.source.database.entity;
-
-import androidx.annotation.NonNull;
-import androidx.room.ColumnInfo;
-import androidx.room.Entity;
-import androidx.room.PrimaryKey;
-
-@Entity(tableName = "combine_document")
-public class CombineDocumentEntity {
-
-    @PrimaryKey
-    @ColumnInfo(name = "id")
-    @NonNull
-    public String id; // ドキュメントID
-
-    @ColumnInfo(name = "title")
-    public String title; // タイトル
-
-    @ColumnInfo(name = "created_at")
-    public String createdAt; // 作成日時
-
-    @ColumnInfo(name = "updated_at")
-    public String updatedAt; // 更新日時
-
-    @ColumnInfo(name = "author")
-    public String author; // 作成者
-
-    @ColumnInfo(name = "parent_id")
-    public String parentId; // 親フォルダID
-}