Based on the method for estimating the noiselevel in power spectrum from wind profiler radar, the spatialtemporal variation of the environmental noiselevel for the WPRs (CFL08) radar at Yanqing, Beijing, is studied statistically by means the sounding data of October to December 2006. During the observation, the environmental noise decreased with the increase of height under 5 km altitude, and the average environmental noise in October was stronger than those in November and December. Two methods for calculating the atmospheric returnsignal power for wind profile radar by SNR (SignaltoNoise Ratio) are presented, and the corrected results are almost the same.