Abstract: An all-fiber coherent laser windfinding radar system was developed, which used a fiber laser to synchronously trigger and transmit the 1.5 μm laser signals that were safe for human eyes. Through the design of all-fiber circular link, high image quality transceiver lens and optical wedge could scan the space cone 45° range vertically, the dual-channel high-reliable double-pass data acquisition and module processing were adopted to achieve the processing and inversion of three-dimensional vector wind field at medium and low altitude. To meet the adaptability of laser radar working in outdoor high and low temperature environment (−25 ℃~40 ℃), the heat source module of laser radar system was simulated. Through the design and development of thermal control module and refrigeration module, the feasibility of working in high and low temperature environment was realized. Finally, the indoor experiment and outdoor wind field calibration experiment of laser radar were carried out. The laser radar can measure the highest wind field height of 3 km, the wind speed accuracy is better than 0.36 m/s, and the wind direction accuracy is better than ±5°.