This　study　details　the　rational　design　and　synthesis　of　Cu2ZnSnS4　(CZTS)-doped　anatase　(A)　heterostructures,　utilizing　earth-abundant　elements　to　enhance　the　efficiency　of　solar-driven　water　splitting.　A　one-step　hydrothermal　method　was　employed　to　fabricate　a　series　of　CZTS-A　heterojunctions.　As　the　concentration　of　titanium　dioxide　(TiO2)　varied,　the　morphology　of　CZTS　shifted　from　floral　patterns　to　sheet-like　structures.　The　resulting　CZTS-A　heterostructures　underwent　comprehensive　characterization　through　photoelectrochemical　response　assessments,　optical　measurements,　and　electrochemical　impedance　spectroscopy　analyses.　Detailed　photoelectrochemical　(PEC)　investigations　demonstrated　notable　enhancements　in　photocurrent　density　and　incident　photon-to-electron　conversion　efficiency　(IPCE).　Compared　to　pure　anatase　electrodes,　the　optimized　CZTS-A　heterostructures　exhibited　a　seven-fold　increase　in　photocurrent　density　and　reached　a　hydrogen　production　efficiency　of　1.1%.　Additionally,　the　maximum　H-2　production　rate　from　these　heterostructures　was　11-times　greater　than　that　of　pure　anatase　and　250-times　higher　than　the　original　CZTS　after　2　h　of　irradiation.　These　results　underscore　the　enhanced　PEC　performance　of　CZTS-A　heterostructures,　highlighting　their　potential　as　highly　efficient　materials　for　solar　water　splitting.　Integrating　Cu2ZnSnS4　nanoparticles　(NPs)　within　TiO2　(anatase)　heterostructures　implied　new　avenues　for　developing　earth-abundant　and　cost-effective　photocatalytic　systems　for　renewable　energy　applications.