To overcome the drawback of small displacement, large pressure fluctuation and unbalanced radial force of a rotary positive displacement pump, the rotating-guide-bar and gear mechanisms assembled driving systems of differential velocity vane pump with the cranks and the guide-bars as active parts are presented in this paper. With variation of the motion characteristic coefficient on the rotating-guide-bar and gear mechanisms assembled driving systems, their motion characteristics and laws are investigated. The basic parameter equations are established and the kinematics characteristics and mechanics performance are analyzed for these two types of driving systems. The results show that the transmission performance of rotating-guide-bar and gear mechanisms assembled driving system with the guide-bars as active parts is superior to that with cranks as active parts.