Abstract: The power dividing stepless speed change transmission system has no less than two power dividing zero points of different nonzero finite values whereat the drives is in the same direction. The system, to a great extent, reduces the branch power, thereby improving the efficiency of the power dividing transmission system expanding speed change range in high efficiency thereof. Examples listed comprise a system with a speed regulating device having two adjusted parts, a system with wheel train, a system with the wheel trains serially connected, a system of serially connected power dividing system and systems separately using a mechanical stepless speed change device, a hydraulic transmission device and a hydrodynamic torque converter as speed regulating devices.