Due to the problem of radial force inherent in traditional gear pump, to enhance the working pressure and expand the application scope for the pump is restricted. By introducing the principle of harmonic gear transmission into the field of gear pump, a new type of gear pump of harmonic style was put forward. The structural, features and working principle of this new gear pump were described, and the mechanism why the radial force balanced was analyzed. It provides a new way for innovative design in gear pumps.