In this paper, the control scheme of a co-axial two-wheel mobile robot by human operation is developed. Two joysticks are introduced considering easy and intuitive operation for the user. Common and differential mode of the tilt angle of joysticks correspond to translational and rotational motion respectively. In order to control translational motion of a two-wheel mobile robot, two kinds of controller, that is, velocity-based controller and torque-based controller are developed. Velocity-based controller is designed based on sliding mode control, which considers pitch angle stability and velocity tracking simultaneously. Torque-based controller is realized by introducing virtual pitch angle disturbance to generate the wheel torque. These two methods are compared via simulation, and results show that the velocity-based controller reduces tracking error against the pitch angle disturbance, whereas the torque-based controller has fast response.