In order to develop the push-the-bit RSS (rotary steerable system), a pushing control system was developed. This system consisted of a 1-wire bus circuit, a contactless transmission unit, a measuring unit, a hydraulic unit and a main-control circuit. Through the 1-wire bus circuit, it could receive electric energy and communicate with the downhole central control system bidirectionally. Based on electromagnetic induction principle, contactless power transmission and signal transmission between rotating part and non-rotating part were carried out. According to the instructions from the ground system, using the force vector decomposition principle, hydraulic pressures in three rib cylinders were calculated. Pressure sensors were used to measure the actual hydraulic pressures in three rib cylinders and the hydraulic pressures were closed-loop controlled. Preliminary experiments of pushing control system were carried out, the functions of power and signal transmissions, the function of pushing control, the performances of high temperature resistance and vibration resistance of this system were verified. This pushing control system achieved the design aim and met the requirements of further experiments.