An electrical servo sinusoidal vibration system of performance test bench is presented for shock absorber which based on the combined control of LabVIEW and Programmable Logical Controller (PLC), then used the servo motor to drive vibration damper test platform, at last realized the controllable of speed and cycle. First of all, according to the《Test method of the automobile cylinder damper platform》to determination the sinusoidal excitation scheme of crank linkage mechanism, then according to the requirements of excitation,the dynamic matching calculation and hardware selection were carried out. At last, the upper computer LabVIEW and lower computer PLC were united and used to programming. The speed calibration and experiment of three cycles are adopted to realize and verify the accurate control of velocity and period under sinusoidal excitation.