A vibration isolation platform is designed for keeping the precise optical instrument to work accurately.By taking displacement sensors with an accuracy of 10 nm as measuring devices, the platform calculates the changed force of the supporting spring by measuring the length change of the spring with the displacement sensor, then it adjusts the force of electromagnet actuator according to the changed force of spring to balance the precise optical instrument to isolate the vibration of base.According to the analysis of theory and simulation, it can satisfy the request of vibration isolation.Furthermore,this method is propitious to the multilevel reduce vibration, for each vibration isolation platform is independent.Experimental results indicate that when the vibration amplitudes of foundation are 0.22,0.20,0.18 and 0.15 mm, the vibration amplitudes of isolation vibration platform is 1.6,1.4,1.2 and 1.0 μm, respectively, which shows proposed method can satisfy the requirement of isolation vibration.