Membrane effect can improve the cracking load and ultimate bearing capacity of the reinforced concrete floor,but there is no complete theory to calculate the influence degree of the membrane effect. In this paper,a multi-group model by the finite element analysis software ANSYS was built. Through contrast analysis,it was found that the membrane effect have a certain improvement on the cracking load and ultimate bearing capacity,the largest of cracking load increase factor can be up to 1. 27,the largest increasing factor of the ultimate bearing capacity can be up to 1. 69.