Abstract: In order to realize the high-precision measurement of nanoscale micro-vibration, a new type of collinear optical heterodyne interference system is designed based on the traditional optical heterodyne interference system. The symmetrical dual optical path is designed by using dual acoustoptic modulator, which greatly reduces the interference of environmental noise. A precision diaphragm is added behind the acoustooptic modulator to filter out stray light and eliminate optical noise. The Faraday polarimeter is used to change the polarization state of the light in measuring the optical path, which not only reduces the optical components, but also makes the optical path easier to adjust. The experimental verification is carried out by simulating vibration of piezoelectric ceramics. The experimental results show that the amplitudes of the two detection signals are 936 mV and 1.1 V respectively, which is about 15 times higher than that of the traditional heterodyne interferometry, and the frequency is 30.12 MHz. The signal waveform is stable and of no distortion, and the anti-noise performance is greatly improved, and the system resolution is 2.1 nm.