The　photogating　effect　based　on　the　vertical　structure　of　a　two-dimensional　material　allows　high-sensitivity　and　broad-spectrum　photodetector.　A　high-sensitivity　photodetector　based　on　the　vertical　heterostructure　of　indium　selenide　(InSe)/molybdenum　ditelluride　(MoTe2)　is　reported,　which　exhibits　excellent　broad-spectrum　detection　capability　from　365　to　965　nm.　The　top　layer　of　InSe　was　used　as　the　grating　layer　to　regulate　the　channel　current,　and　MoTe2　was　used　as　the　transmission　layer.　By　combining　the　advantages　of　the　two　materials,　the　photodetector　has　a　fast　response　time　of　21.　6　ms　and　achieves　a　maximum　detectivity　of　1.05　x　1013　Jones　under　365　nm　laser　irradiation.　Under　the　illumination　of　965　nm,　the　detectivity　still　achieves　the　order　of　109　Jones.　In　addition,　the　InSe/MoTe2　heterostructure　exhibits　an　external　quantum　efficiency　of　1.　03　x　105%,　demonstrating　strong　photoelectric　conversion　capability.