diff --git a/src/main/java/cactusServer/entities/Instance.java b/src/main/java/cactusServer/entities/Instance.java
index ce51517..5874cce 100644
--- a/src/main/java/cactusServer/entities/Instance.java
+++ b/src/main/java/cactusServer/entities/Instance.java
@@ -140,10 +140,10 @@
 	}
 
 	public HashMap<String, Object> createObject(Position3D position, Velocity3D velocity,
-			AngularVelocity3D angularVelocity, Quaternion3D angle, Attribute attribute, String model) {
+			AngularVelocity3D angularVelocity, Quaternion3D angle, Attribute attribute, int modelID) {
 		String id = RandomStringGenerator.generateUniqueString(Object.UNIQUE_ID_LENGTH,
 				RandomStringGenerator.ALPHA_NUMERIC, objMap.keySet());
-		Object object = new Object(position, velocity, angularVelocity, angle, attribute, model);
+		Object object = new Object(position, velocity, angularVelocity, angle, attribute, modelID);
 		objMap.put(id, object);
 		universe.place(object.getPlaceable());
 		HashMap<String, Object> returnedMap = new HashMap<>();
diff --git a/src/main/java/cactusServer/entities/Object.java b/src/main/java/cactusServer/entities/Object.java
index d3ae812..f2e55d1 100644
--- a/src/main/java/cactusServer/entities/Object.java
+++ b/src/main/java/cactusServer/entities/Object.java
@@ -1,10 +1,12 @@
 package cactusServer.entities;
 
+import org.ntlab.radishforandroidstudio.framework.model3D.Model3D;
 import org.ntlab.radishforandroidstudio.framework.model3D.Position3D;
 import org.ntlab.radishforandroidstudio.framework.model3D.Quaternion3D;
 import org.ntlab.radishforandroidstudio.framework.physics.AngularVelocity3D;
 import org.ntlab.radishforandroidstudio.framework.physics.Velocity3D;
 
+import cactusServer.models.ObjectModelManager;
 //import framework.model3D.Position3D;
 //import framework.physics.AngularVelocity3D;
 //import framework.physics.Velocity3D;
@@ -16,7 +18,7 @@
 	private AngularVelocity3D angularVelocity;
 	private Quaternion3D angle;
 	private Attribute attribute;
-	private String model;
+	private Model3D model;
 
 	@JSONHint(ignore = true)
 	public static final int UNIQUE_ID_LENGTH = 12;
@@ -27,13 +29,13 @@
 	}
 
 	public Object(Position3D position, Velocity3D velocity, AngularVelocity3D angularVelocity, Quaternion3D angle,
-			Attribute attribute, String model) {
+			Attribute attribute, int modelID) {
 		setPosition(position);
 		setVelocity(velocity);
 		setAngularVelocity(angularVelocity);
 		setAngle(angle);
 		setAttribute(attribute);
-		setModel(model);
+		setModel(modelID);
 	}
 
 	public Position3D getPosition() {
@@ -56,7 +58,7 @@
 		return attribute;
 	}
 
-	public String getModel() {
+	public Model3D getModel() {
 		return model;
 	}
 
@@ -80,8 +82,8 @@
 		this.attribute = attribute;
 	}
 
-	public void setModel(String model) {
-		this.model = model;
+	public void setModel(int modelID) {
+		this.model = ObjectModelManager.getInstance().getObject(modelID);
 	}
 
 	public static class Attribute {
diff --git a/src/main/java/cactusServer/resources/ObjectsRest.java b/src/main/java/cactusServer/resources/ObjectsRest.java
index d7dc3da..6d213ab 100644
--- a/src/main/java/cactusServer/resources/ObjectsRest.java
+++ b/src/main/java/cactusServer/resources/ObjectsRest.java
@@ -51,10 +51,10 @@
 	public String createObject(@PathParam("instanceId") String instanceId,
 			@FormParam("position") Position3D position, @FormParam("velocity") Velocity3D velocity,
 			@FormParam("angularVelocity") AngularVelocity3D angularVelocity, @FormParam("angle") Quaternion3D angle,
-			@FormParam("attribute") Attribute attribute, @FormParam("model") String model) {
+			@FormParam("attribute") Attribute attribute, @FormParam("model") int modelID) {
 		Instance instance = Instances.getInstance().getInstance(instanceId);
 		HashMap<String, Object> idMap = instance.createObject(position, velocity, angularVelocity, angle, attribute,
-				model);
+				modelID);
 		HashMap<String, Object> uriMap = new HashMap<>();
 		for (String id : idMap.keySet()) {
 			String uri = (InstancesRest.INSTANCES_URI + "/" + instanceId + "/objects/") + id;
diff --git a/src/main/java/cactusServer/utils/App.java b/src/main/java/cactusServer/utils/App.java
index 9bdf828..0294f21 100644
--- a/src/main/java/cactusServer/utils/App.java
+++ b/src/main/java/cactusServer/utils/App.java
@@ -79,7 +79,7 @@
 		Instances.getInstance().getPlayers().put("player2", player2);
 		// �_�~�[�I�u�W�F�N�g
 		Instances.getInstance().getInstance("test1").createObject(new Position3D(0, 0, 0), new Velocity3D(),
-				new AngularVelocity3D(), new Quaternion3D(), new Attribute(true,1), new String());
+				new AngularVelocity3D(), new Quaternion3D(), new Attribute(true,1), 0);
 		// �m�F�p
 		// String player1Encode = JSON.encode(player1, true);
 		// String player2Encode = JSON.encode(player2, true);