The invention discloses a stannous sulfide and indium sulfide thin film solar cell and a preparation method thereof. The stannous sulfide and indium sulfide thin film solar cell sequentially comprises a base 1, a metal nanowire 2, an N type beta-indium sulfide window layer 3, a molybdenum disulfide buffer layer 4, a P type stannous sulfide absorption layer 5 and a metal electrode 6 from bottom to top. The stannous sulfide and indium sulfide thin film solar cell has the advantages that firstly characteristics of energy gaps of stannous sulfide, molybdenum disulfide and beta-indium sulfide are fully utilized, and stannous sulfide, molybdenum disulfide and beta-indium sulfide are respectively used as the absorption layer, buffer layer and window layer of the solar cell, so that full absorption of sunlight is benefited; secondly, the characteristic that stannous sulfide, molybdenum disulfide and beta-indium sulfide belong to sulfides is utilized, and lattice mismatching among stannous sulfide, and molybdenum disulfide and beta-indium sulfide is reduced, so that defect state density is reduced, recombination of photon-generated carriers is reduced, and transmission of the carriers is benefited; and thirdly, the metal nanowire is used for replacing the traditional conductive thin film, film resistance is greatly reduced, lateral collection of the carriers is benefited, and photoelectric conversion efficiency of the solar cell is greatly improved.