AgIn 5 S 8 and AgIn 5 S 8 /TiO 2 heterojunction nanocomposite with efficient photoactivity for H 2 production were prepared by a low-temperature water bath deposition process. The resultant AgIn 5 S 8 shows an absorption edge at ∼720 nm, corresponding to a bandgap of ∼1.72 eV, and its visible-light-driven photoactivity (100.1 μmol h −1 ) for H 2 evolution is 9 times higher than that (11 μmol h −1 ) of the product derived from a hydrothermal process, while the obtained AgIn 5 S 8 /TiO 2 heterojunction nanocomposites prepared by using commercially available TiO 2 nanoparticles (P25) as TiO 2 source exhibit remarkably improved photoactivity as compared to the pristine AgIn 5 S 8 , and the AgIn 5 S 8 /TiO 2 nanocomposite with molar ratio of 1:10 shows a maximum photocatalytic H 2 evolution rate (371.1 μmol h −1 ), which is 4.3 times higher than that (85 μmol h −1 ) of the corresponding AgIn 5 S 8 /TiO 2 nanocomposite derived from a hydrothermal method. This significant enhancement in the photocatativity of the present AgIn 5 S 8 /TiO 2 nanocomposite can be ascribed to the better dispersion of the AgIn 5 S 8 formed on TiO 2 nanoparticle surfaces and the more intimate AgIn 5 S 8 /TiO 2 heterojunction structure during the water bath deposition process under continuously stirring as compared to the corresponding nanocomposite derived from a hydrothermal method. This configuration of nanocomposite results in fast diffusion of the photogenerated carriers in AgIn 5 S 8 towards TiO 2 , which is beneficial for separating spatially the photogenerated carriers and improving the photoactivity. The present findings shed light on the tuning strategy of spectral responsive region and photoactivity of photocatalysts for efficient light-to-energy conversion.