Base on the strain rate calculated by the network project GPS data obtained during 1999~2009, the characteristics of crustal stress filed, strain field and the horizontal activity of the crust were studied in Chinese mainland. The results show that the primary direction of compressive stress of Qinghai-Tibetan inferior plate tended to radial lines along the southern oft-com:office:smarttags" />Tibet and the Assam tectonic node. The primary direction of Xinjiang inferior plate varies from SN to NE from West to East. The primary direction of crustal compressive stress of East China varies from NEE to almost EW, and then varies to SEE from North to South. Obviously, the strength of main compressive stress in western China is stronger than in the East China. The crustal activity of western China was stronger than that of East China, while the activity of southern China is stronger than that of North China.