Laser self-mixing interferometer has advantages of simple architecture, compact size, naturally self-aligned optical characteristics, and low cost. It can replace conventional interferometers to measure displacement, distance, velocity, vibration and other physical quentities. When it is used in the micro-electro-mechanical system (MEMS) dynamic measurement, a system with simple architecture and low cost can be developed, which is suitable for fast and accurate characterization measurement of vibrating micromachined devices. Based on the three-mirror cavity model, self-mixing interference measurement principle is discussed. The laser self-mixing interference MEMS dynamic measurement system is designed, and the key components are discussed detailedly. Experiments are studied when the target moves in different forms. The results prove that laser self-mixing can measure target’s different movement forms. The laser self-mixing interference measurement system can support MEMS dynamic measurement.