Generally， a sufficient output force is crucial to obtain maximum performance in an active vibration isolation system. To resolve conflicts between output force and maximum performance， an active double layer vibration isolation system （DLVIS） is designed by applying a multi-objective optimization method with genetic algorithms. Theoretical analysis on the active DLVIS is carried out under different excitations and probe into the influence of parameters on the output force. Furthermore， a comprehensive performance evaluation index is defined with weight coefficients and the optimal parameters being achieved. Besides， a fuzzy proportional integral derivative algorithm is proposed to illustrate the active vibration isolation system after optimization. A numerical example is given to evaluate the effectiveness of the optimized active DLVIS. The results demonstrate that the displacement response of upper stages， relative displacement response between the upper and lower stages， and output force can be substantially reduced by 32.7%， 67.5% and 55.4%， respectively， after optimization. Therefore， the optimized active DLVIS is a feasible power-saving solution for vibration control.