Abstract: Noise always exists in photoelectric signal detected by laser Doppler velocimeter (LDV). A new method of signal processing was proposed in order to eliminate the noise interference and enhance the measurement accuracy of LDV. The least mean square(LMS) adaptive filter technology was applied in the signal detection system of LDV. By processing the Doppler signal, we greatly minished the interference of noise. The simulation and experiment results indicate that this technology effectively increases the signal to noise ratio(SNR) of Doppler signal, reduces the system-s demand for SNR of signal, and obviously improves the noise-proof ability, the sensibility,as well as the measurement accuracy of LDV system. This application creates conditions for the design of high accuracy LDV.