Relief amplitude is used as one of the terrain factors to describe the macroscopic topographic change, which can be used as one of the topographic indexes for evaluation of regional soil and water loss. The Loess Plateau, Sichuan basin, Hengduan mountainous region, Southeast hills, Shandong hills and northeast regions 6 typical samples were selected based on dynamic effect model(DEM) of 1000 resolution of China, relief amplitude was extracted with the 6 methods of local elevation range, local standard deviation, the ratio of surface area and the projected area, RUGN, the vector method and relief degree of land surface(RDLS). The results of extraction were analyzed, and then the amounts of information were calculated. The results showed that local standard deviation and local elevation range were the two better methods, and different regions have different suitability.