For a new type of radial plunger variable hydraulic pump, a testing system of computer-aided test （CAT） test stand was developed and designed. Based on the idea of machine, electricity, liquid and instrument integrated computer automatic control, the hydraulic system circuit design, hardware design and software design for hydraulic pump CAT test stand were carried out. The results show that the designed test system has strong function, high efficiency, high precision, high degree of automation, and convenient operation. It achieves the expected effect and has certain universality.