A laser coherent detection system, operating at 1550 nm and all fiber designed, is set up and a large aperture lens of 200 mm is used to collect scattered light. Using this system, the micro-Doppler effect of moving target is detected. The results of the signal analysis in spectrum analysis and time-frequency analysis show that time-frequency analysis is effectively to the feature extraction of micro-Doppler signal of moving target, which is time-varying. The different targets of 20~2000 Hz can be identified and classified by these characteristics. It provides an effective method of the feature extraction, classification and recognition of the target.