The spacetime distribution features of the atmospheric precipitable wa ter vapor over the Hebei province are preliminarily analyzed using the GPS data of Shijiazhuang, Zhangjiakou and Qinhuangdao from Apr. to Nov. 2005, which were processed b y GAMIT software .It indicates that the precipitable water changes remarkably with seasons and precipitation mostly occurs in the period when precipitable w ater is larger than its threshold value. It also suggested that different variat ion characteristics are correspondent to the different weather systems.