Abstract: At present, the bearing capacity calculation is based on three-items superposition method proposed by Terzaghi in study or practice. The three items which constituing the bearing capacity are the cohesion of the soil, the surcharge load beside the foundation and the weight of the soil Since the soil is neither linear nor elastic material,it is not a good choice to use the superposition method in theory. It maybe a good choice to directly calculate the bearing capacity with all the influnce factors taking into considered. To analyze the difference of the two rnothods mentioned above, the multi-block upper hound method is employed. The calculation results based on the two methods are presented here,and the difference is discussed. With the envelops obtained by the multi-block upper hound method, the cause of the difference for the two methods is demonstrated.