LaNiO3/CdS　heterojunction　photocatalysts　are　constructed　by　compositing　LaNiO3　nanoparticles　with　commercially　available　CdS,　and　are　used　for　efficient　photocatalytic　splitting　of　H2O　with　visible　light.　The　LaNiO3/CdS　hybrids　are　characterized　systematically　using　a　series　of　physicochemical　techniques.　The　photocatalytic　activity　of　the　perovskite　hybrids　is　examined　by　H2　evolution　with　Na2S-NaSO3　as　the　hole　scavenger.　The　optimized　LaNiO3/CdS　sample　without　the　assistance　of　any　cocatalyst　(e.g.,　Pt)　delivers　a　high　H2　production　rate　of　74　μmol　h−1　(e.g.,　3700　μmol　h−1　g−1),　which　is　substantially　superior　to　the　individual　LaNiO3　and　CdS.　Besides,　the　composite　photocatalyst　also　manifests　high　stability.　The　greatly　improved　H2　production　performance　of　LaNiO3/CdS　is　attributed　to　the　facilitated　separation　and　transport　of　photoinduced　charge　carriers,　as　evidenced　by　photoelectrochemical　(PEC)　analyses,　such　as　photoluminscence　spectroscopy,　transient　photocurrent　responses,　and　electrochemical　impedance　spectroscopy.　Moreover,　a　probable　photocatalytic　mechanism　of　the　H2　evolution　reaction　is　proposed　on　the　basis　of　the　results　of　the　catalysis　evaluation　and　PEC　tests.　©　2018　Wiley-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim