One　of　the　major　challenges　of　immune　checkpoint　blockade　(ICB)　is　the　poor　penetration　of　antibody　for　solid　tumor　treatment.　Herein,　peptides　with　deeper　penetration　capability　are　used　to　develop　a　click　reaction-assisted　peptide　immune　checkpoint　blockade　(CRICB)　strategy　that　could　in　situ　construct　assemblies,　enabling　enhanced　accumulation　and　prolonged　PD-L1　occupancy,　ultimately　realizing　high-performance　tumor　inhibition.　First,　the　free　DBCO-modified　targeting　peptide　(TP)　efficiently　recognizes　and　binds　PD-L1　in　a　deep　solid　tumor.　Upon　a　reagent-free　click　reaction　with　a　subsequently　introduced　azide-tethered　assembled　peptide　(AP),　the　click　reaction　results　in　spontaneous　self-aggregation　in　situ　with　enhanced　accumulation　and　prolonged　occupancy.　In　addition,　the　penetration　of　TP-AP　(121.2　+/-　15.5　mu　m)　is　significantly　enhanced　compared　with　that　of　an　antibody　(19.9　+/-　5.6　mu　m)　in　a　solid　tumor　tissue.　More　importantly,　significant　immunotherapy　effects　and　negligible　side　effects　are　observed　in　4T1　and　CT26　tumor-bearing　mice　models　treated　with　TP-AP,　suggesting　the　high-performance　tumor　inhibition　attributed　to　the　CRICB　strategy.　In　summary,　this　CRICB　strategy　manifest　the　preferable　effects　of　immune　checkpoint　blockade,　thereby　extending　the　biomedical　application　of　assembling　peptides.