To obtain multi-degree-of-freedom micro-vibration information of an optical platform, a three-degree-of-freedom dynamic micro-vibration measurement system based on plane mirror dual-frequency laser interference is designed. The system utilizes the laser Doppler effect to obtain the three-point displacement information of the measuring mirror by using three measuring axes; calculates the overall displacement, torsion angle, and pitch angle information of the measuring mirror; and detects the three-degree-of-freedom micro-vibration in real time, thereby providing a basis for micro-vibration compensation control of the optical system. The uncertainty of the micro-angular vibration measurement system is analyzed, and an uncertainty model is established, which provides a theoretical basis for further improving the accuracy of the system and also lays a solid foundation for application of the system in the field of calibration and metrology. During the experiment, a high-precision seismometer was used to measure the platform simultaneously and, by comparison with the system translation measurement results, the measurement accuracy of the system was verified. The displacement resolution of the system is 5 nm, the torsion resolution is 5.05 rad, and the pitch resolution is 4.69 rad. The system has the advantages of multiple degrees of freedom, noncontact operability, high resolution, and traceability.