Abstract: In order to realize the design of feedback control circuit of space micro gravity active vibration isolation system, 6 laser displacement sensors were used to measure the displacements of 3 orthogonal positioning surfaces of vibration isolation platform. 3-D position and attitude were solved. And the derivation process was also given. The method was verified by numerical simulation and experimental test. The source of error and its influence on the result of calculation were analyzed. The relationship between error influence factors and calculation error was given. The results show that this algorithm can accurately calculate the 3-D position and attitude of a vibration isolation platform. The theoretical calculation error is less than 30μm. This research has some practical value and prospects for the design of feedback control loop based on displacement measurement.