A virtual reality (VR) system including a VR box, a system server and a wearable accessary is provided. The VR box detects a biometric characteristic to identify a user ID according to the biometric characteristic, and outputs an ID signal associated with the identified user ID. The system server receives the ID signal from the VR box, and transmits video stream to the VR box to be shown thereon. The wearable accessary detects movement of the wearable accessary after receiving the ID signal from the VR box, and sends a control signal to the system server to change image content in the video stream according to the detected movement of the wearable accessary.