diff --git a/src/main/java/cactusServer/entities/Instance.java b/src/main/java/cactusServer/entities/Instance.java
index add0c54..8ba1aad 100644
--- a/src/main/java/cactusServer/entities/Instance.java
+++ b/src/main/java/cactusServer/entities/Instance.java
@@ -34,7 +34,7 @@
 public class Instance extends Entity {
 	private String name;
 	private State state;
-	private String stageID;
+	private int stageID;
 
 	private Universe universe;
 	private Ground stage;
@@ -48,7 +48,7 @@
 		// JSONDecode���̌Ăяo���p
 	}
 
-	public Instance(String name, State state, String stageID) {
+	public Instance(String name, State state, int stageID) {
 		setName(name);
 		setState(state);
 		setStageID(stageID);
@@ -59,7 +59,7 @@
 		universe = new Universe();
 
 		// stageURI�����ɂ��ēǂݍ��ރX�e�[�W�̃t�@�C����(���΃p�X)�����\��
-		String stageFileName = stageID;
+		String stageFileName = "";
 
 		// �X�e�[�W��3D�f�[�^��ǂݍ��ݔz�u����
 		Object3D stageObj;
@@ -80,7 +80,7 @@
 		return state;
 	}
 
-	public String getStageID() {
+	public int getStageID() {
 		return stageID;
 	}
 
@@ -124,7 +124,7 @@
 		this.state = state;
 	}
 
-	public void setStageID(String stageURI) {
+	public void setStageID(int stageURI) {
 		this.stageID = stageURI;
 	}