Based on the sinusoidal phase-modulation laser self-mixing interference technique,the precision measurement of the small vibration on the rough surface is realized,such as speaker surface or white paper.The 532nm solid-state laser is selected as the laser light source.And the sinusoidal phase-modulation of the laser is achieved based on the electro-optical modulator,with a corresponding modulation frequency of 251kHz.By using the mixer/filter circuits,the high signal- to-noise ratio sinusoidal and cosine function laser power oscillation signals caused by displacement change are extracted from the self-mixing interference optical fringes modulated by sinusoidal phase-modulation,further obtaining the phase change of the laser caused by displacement change.Therefore,the vibration and displacement of external targets can be efficiently calculated from the phase change of the laser.By comparing the measurement results with a precision displacement platform with an accuracy of 50nm,the two instruments showed good agreement,and the performance of the laser self-mixing interferometer was experimentally verified.The new technology can provide reliable technical support for high-precision low-frequency micro-vibration and micro-displacement measurement.