The photvoltaic power system has received considerable attention as the petroleumalterative energies to the environmental problems in the wored scale. $CuLnSe_2$is one ofthe most promising materials for the fabrication of large-area modules and low cost photovoltaic devices. Sulfur solute CuInSe2 thin films were prepared by RF sputtering using powder targer which were previously compacted by powder of $Cu_2Se, ;In_2Se_3, ;Cu_2S, ;and;In_2S_3$ in various ratios. The results induicated that the sulfur ratio, the(112) texture, and the energy band gap were increased by the increase of the S/(S+Se) that was controlled by stoichiometric compound. The energy band gap can be shifted from 1.04eV to 1.50eV by abjusting the S/(S+Se) ratio, which maich it possible to obtain perfect match to the solar spectrum.