In order to test the influence of the vibration induced by the random o cean waves on thperformance and reliability of shipborne equipment, an environmental simulation experiment is conducted. In the experiment, a ship simulator wi th six degrees of freedom is used to generate the random wave spectrum, in which a double closed loop control system, including the time domain loop control and the frequency domain loop control, is designed to obtain the r andom wave spectrum, and the real time forward solution to the motion of the output of the simul ator according to its input is used so as to omit the output measurement. The signal generation technology of random waves is studied based on the spectr um equalization and time domain randomization. Experimental results show that the ship motion simulator can generate the random wave spectrum at its output platform with the accuracy of ±１dＢin the frequency domain.