Silver indium sulfide (AgInS2) thin films have been prepared by the spray pyrolysis technique using silver acetate, indium acetate, and N,N-dimethylthiourea as precursor compounds. Depending on the film preparation conditions, AgInS2 thin films are obtained which could be candidates to be used in photovoltaic devices. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) compositional studies were done on films formed at different substrate temperatures (T (s)) and Ag:In:S ratios in the starting solutions. When Ag:In:S ratios are 1:1:1, 1:0.25:2, and 1:1:2, XRD patterns of the thin films indicated that the crystallographic structure is mainly chalcopyrite AgInS2. An additional phase, acanthite Ag2S, appeared when the depositions where done at low T (s). EDS analysis showed that AgInS2 films near stoichiometric composition were obtained by using an atomic ratio of Ag:In:S = 1:1:2 in the starting solution and T (s) = 400 degrees C.