This paper utilizes the observed data at three sites, namely Jinhua, Hefei, and Lanzhou sites, for the same period to carry out planetary boundary layer height (PBLH) inversion, statistics, and analysis. The research results show that the PBLHs over Jinhua, Hefei, and Lanzhou have characteristics of seasonal and diurnal variation. The PBLHs over Jinhua and Hefei are lower than that over Lanzhou in spring, summer, and autumn. The starting time of the rise and fall of boundary layer height over Lanzhou is in well correspondence with the time of sunrise and sunset, whereas the height over Hefei does not increase significantly until a few hours after sunrise. Jinhua, Hefei and Lanzhou have the highest monthly mean diurnal PBLHs in September, August, and June, respectively, and the corresponding monthly mean maximum mixed layer heights are in September, August, and July, respectively. Studying the spatial and temporal distribution pattern of the PBLH can provide further reference for research of air pollution prevention and control, weather forecasting, and climate prediction.