Abstract: Based on the analysis of the key problems about long distance kinematic GPS data processing,we caculated the displacements of the stations in Sichuan GPS network using the data before and after 5.12 Wenchuan Earthquake.The accuracy of long distance kinematic GPS data processing was analyzed.Kinematic deformation series of Mianyan and Pixian were obtained using Yaan as a reference station.Decomposing the deformation series into mountain Longmen fault direction and its orthogonal direction,the kinematic deformation features of several stations were obtained.Results about kinematic crustal deformation of Wenchuan Earthquake show that Mianyan and Pixian move towards northwest with small amplitude of swing during the earthquake.The maximum kinematic displacements of Mianyang and Pixian were 49.2 cm and 114.1 cm respectively.In the vertical direction,the height of Mianyan decreased after uplifting 10 cm.The height of Pixian fluctuated periodically and the fluctuation range was ±13 cm.