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The electronic structures of cubic structure of ABX3(A=CH3NH3, Cs;B=Sn, Pb;X=Cl, Br, I) are analyzed by den-sity functional theory using the Perdew–Burke–Ezerhof exchange–correlation functional and using the Heyd–Scuseria–Ezerhof hybrid functional. The valence band maximum (VBM) is found to be made up by an antibonding hybridization of B s and X p states, whereas bands made up by theπ antibonding of B p and X p states dominates the conduction band minimum (CBM). The changes of VBM, CBM, and band gap with ion B and X are then systematically summarized. The natural band offsets of ABX3 are partly given. We also found for all the ABX3 perovskite materials in this study, the bandgap increases with an increasing lattice parameter. This phenomenon has good consistency with the experimental results.