In the perception-assist, user's dangerous motion is changed to safety motion when there is a possibility of accident such as the collision between user's body parts and obstacles. On the other hand, the joint motion of a human can be changed by using vibration stimulation on the tendon of muscle. By using this motion change method, there is a possibility that perception-assist by using vibration stimulation can be realized. The aim of this study is to investigate the effects of vibration stimulation to elbow joint motion under elbow joint loaded conditions. Vibration stimulation was added to the tendon of biceps brachii during elbow joint extension motion in the experiment of this study. During the experiment, subject's elbow joint load condition is changed by using weight which is grasped in their vibrated arm's hand. The results show that motion change can be generated in all trials with all subjects under the loaded condition. Furthermore, as the weight increases, the amount of elbow joint motion changing rate decreases.