The fundamental working theory of the Doppler wind lidar (DWL) based on Fabry-Perot (F-P) etalon is introduced.The typical detection data of DWL system is provided.The factors depressing DWL wind detection accuracy are analyzed,including background light intensity,operation state of detector,the locking state of laser frequency,the environment of seed laser,deformation of the receiver caused by sudden changes of the workplace temperature,and so on.Strong background light will cause the system signal-to-noise ratio decreases rapidly.Saturated detectors will be in nonlinear working state and generate invalid data.The lose lock on laser will cause wind profile to move parallel,the instability of seed laser environment temperature will cause the laser jump phenomenon.After overcoming the factors one by one,the wind speed variation of DWL with balloons is within 1.4 m/s,wind direction deviation is within 2.2°.