The existing systems of hand rehabilitation always design different rehabilitation medical apparatus and systems according to the patients’ needs. This kind of system always contain problems such as complexity, using only single training programs, inconvenient to wear and high cost. For these reasons, this paper uses gesture recognition technology and augmented reality technology to design a simple and interactive hand rehabilitation supplementary system. The system uses a low-cost, non-contact device named Leap Motion as the input device, and Unity3D as the development engine, realizing three functional modules: conventional training, AR game training and auxiliary functions. This rehabilitation training project with different levels of difficulty increases the fun and challenge of the rehabilitation process. Users can use the system to assist the treatment activity of hand rehabilitation anytime and anywhere. The system, which has good application value, can also be used in other physical rehabilitation fields.