This paper presents a teleoperation system to control mobile robot remotely. The system architecture is based on network technology. To get a synthetical knowledge of the robot and its working environment, besides the real video feedback from the robot vision system, a multiple viewpoints virtual scene of the robot and its worksite is constructed. It can present images in first person and third person viewpoints. To complete a complex task, operators can conveniently select different viewpoints to monitor the robot or target for different task process. Multiple input devices such as keyboard, mouse and joystick are adopted to input the commands, and different operational modes are designed to control the robot in different task. Finally, the effectiveness of the teleoperation system is illustrated by experiments that the operator manipulates mobile robot.