Electric wheelchair is one of the equipment to be used by the incapacitated and disable people. Constant exposure to vibration affects human comfort and health. Reducing the vibrations transmitted to the human body is important in the electric wheelchair design and becomes a healthcare industry demand. This paper deals with the study on vibration control of the electric wheelchair suspension system. A generalized model of the electric wheelchair suspension, including the biodynamic model of seated human body is presented. In order to achieve optimal suspension performance, an active control for wheelchair suspension is designed based on H-infinity control criterion. Numerical simulations are carried out to demonstrate the effectiveness of the proposed wheelchair suspension system. The simulation results show that the proposed control system can effectively attenuate the vibration amplitude and improve the wheelchair suspension performance. This control system could be used for electric wheelchair design and assist with improving human comfort.