For analyzing the situation that electron oblique incidence through graphene, it is assumed that graphene layer is as a barrier.The width of the barrier is D and the height is V0.The energies of the electrons that pass through from the incidence layer, the graphene layer, and the transmissive layer are set to E1,E2 and E3 (E1>E2>E3).The transmittance of the electrons is obtained by Schrdinger equation and the continuities of the wave function and its derivative at x=0 and x=D.The figures of the transmissive are drawn using Matlab.The results show us three aspects.The first one is that the transmittance is independent of the incident angle but related to energy.The second one is that the higher the incident energy is, the greater the energy is after passing through the barrier, that is, the better the transmittance.The narrower the barrier width is, the higher the transmission energy is.The third one is that the transmitted energies are 555％, 320％, 152％ of the height of the barrier at the widths of the barrier are 1, 2, 3 times of the length of the tunneling effect when the incidence energy is the 07 times of the height of the barrier.