The displacement velocity data of 28 GPS stations in TianjinBeijing area under the ITRF2005 are further processed and analyzed as a whole. In a local area, it is unavoidable that local crust moves rigidly on the whole relative to ITRF2005, and this disturbs us in interpreting the magnitude and characters of crust relative deformation inside the area. The method for dividing the parallel components of the velocity vectors is studied. Through the analysis
of practical data, it is concluded that with both of parallel component average method and Euler vectors method,
good results can be obtained respectively from the data of 28 GPS stations in Tianjin and Beijing area,
however, the parallel components average method is of more simplicity and clarity.