The invention relates to an automobile hydraulic electric power steering reliability test bench and program control test method. An input system comprises a servo motor, a reducer and a universal joint connected with the input end of a steering gear; an output system comprises a linear hydraulic cylinder with two functions of driving and load simulation, the front pole of a hydraulic cylinder piston is provided with a pressure sensor and connected with the rocker arm of the output end of the steering gear by a coupler with a joint bearing. An eccentric shaft, an eccentric bushing and a variable frequency motor are arranged at the inner bore of the rear lug of the hydraulic cylinder to form an automobile vibration simulation system, so as to simulate real vibration of rugged road surface. The hydraulic cylinder is compact and simple in structure, system integration is high and usable range is wide. The joint bearing causes the installation to be convenient. The hydraulic loop includes a throttle valve, thus speeding up oil-taking. An industrial personal computer, a motion control card and a data acquisition card are used, so that system stability is high, measurement accuracy is high, and response speed is fast. Curves and process control can be displayed in real time, and automatic save, plotting and printing can be realized. The test bench set can complete all reliability tests of fatigue, wear, forced steering, inverse overload and overpressure.