Modifying　titanium　dioxide　(TiO2)　with　graphdiyne　(Gry)　makes　that　the　absorption　range　of　UV-vis-nIR　spectrum　expands　in　visible　light　area.　However,　in　traditional　methods,　the　two　materials　are　combined　by　hydrothermal　process.　In　this　paper,　in-situ　synthesis,　which　monomer　directly　polymerizes　on　the　surface　of　TiO2　instead　that　polymer　and　TiO2　combined　by　hydrothermal　method,　is　employed　to　get　hybrid　materials.　In　the　process,　TiO2　thin　film　was　deposited　on　the　glass　slide　followed　by　being　enfolded　in　copper　(Cu)　foil　to　initiate　polymerization　and　synthesize　Gry　on　the　surface　of　TiO2　directly.　It　turns　out　that　with　co-catalyst　Platinum　(Pt)　the　efficiency　of　TiO2-Gry　with　introduction　of　only　1.9　wt%　Gry　is　12.6%　higher　than　the　efficiency　of　TiO2　under　same　test　conditions.　The　improvement　is　attributed　to　band　structure　of　the　combined　material　and　efficiency　of　charge　transfer.　In　this　system,　Gry　acts　as　an　excellent　medium　for　charge　transfer,　which　benefits　from　its　intrinsic　property　and　effective　contact　with　TiO2　by　this　synthesis.　The　work　points　out　a　new　way　to　get　well-combined　platelike　photocatalyst　on　transparent　substrate.　It　gives　a　promising　prospect　for　practical　photocatalysis　in　the　future　that　the　quantity　and　mass　ratio　of　combined　materials　can　be　recorded　and　modified.　©　2022　Hydrogen　Energy　Publications　LLC