Uncertain molecular targets and a complex immune-suppressive tumor microenvironment (TME) present significant challenges for triple-negative breast cancer (TNBC) treatment. This study develops a light-triggered biomimetic nanodelivery system that enables remotely controlled gene editing-assisted TME remodeling and enhanced cancer immunotherapy. The nanosystem integrates a semiconductor polymer with second near-infrared (NIR-II) fluorescence imaging capabilities and CRISPR/Cas9 ribonucleoprotein (RNP) targeting programmed cell death ligand 1 (PD-L1), linked via a singlet oxygen ( 1O 2)-cleavable thioketal (TK) linker. Photosensitizer Ce6 in the nanoparticles generates 1O 2 under irradiation, triggering TK linker cleavage and subsequent Cas9 RNP release. Concurrently, photodynamic therapy (PDT) induces immunogenic cell death (ICD) by promoting tumor-associated antigen release. The combination of PDT-activated ICD and PD-L1 pathway blockade synergistically amplifies immune responses and reprograms the immune-suppressive TME. Utilizing tumor cell membrane camouflage, the nanoparticles achieve homologous tumor targeting under NIR-II imaging guidance while maintaining biocompatibility and precise tumor accumulation. This integrated platform demonstrates enhanced antitumor efficacy through coordinated immune activation and TME modulation, providing a safe and effective strategy for TNBC clinical management.