In view of nonlinear distribution characteristics of wind direction and wind speed with increase of height,as well as non-meteorological interference factors of wind profiler radar in engineering practices,a nonlinear method,namely Extended Kalman Filter (EKF) is proposed in this paper for data filtering of wind profiler radar.Using first-order Taylor expansion and combining with the classic Kalman Filter (KF),EKF method linearizes the nonlinear equations and changes the nonlinear filter into an approximately linear filter.The experimental results indicate that this method can effectively remove the noise of wind data and well reflects its nonlinear characteristics.EKF is better for data processing of wind profiler radar than traditional KF and has some engineering application prospects.