This paper sets up 5 Census database in 1953,1964,1983,1990,2000 based on GIS. The population gravity centers of
main nationalities were calculated using gravity model in 1953, 1964,1983,1990,2000. Then, the characteristics and the
influence factors of the moving of the minority population are analyzed. Study results show that population gravity
center move to capitals are obvious. The move velocities of minorities' population gravity centers are slowdown, while
the move velocities of HAN is Accelerated. Movement distances of
east-west direction are generally greater than that of
the north-south direction. The population gravity center are continued moving to southeast all the while. Finally, the
factors of Natural conditions, Economic development, Policies as the mainly reasons were discussed.