We have synthesized SnS:Bi thin films using a novel method based on sulphurization of the metallic precursors species. The films were characterized through spectral transmittance and X-ray diffraction (XRD) measurements to determine both, the optical constants and structural properties. The studies revealed that the SnS:Bi films tend to grow with a mixture of the SnS and Bi2S3 phases. It was also found that the SnS:Bi films present an absorption coefficient greater than 104cm-1 and an energy band gap ranging from 1.37 to 1.47 eV, indicating that this compound has good properties to perform as absorber layer in thin film solar cells.