Immunotherapy, particularly immune checkpoint blockade (ICB) therapies, has revolutionized oncology. However, it encounters challenges such as inadequate drug accumulation and limited efficacy against "cold" tumors characterized by lack of T cell infiltration and immunosuppressive microenvironments. Here, a controlled antibody production and releasing nanoparticle (CAPRN) is introduced, designed to augment ICB efficacy by facilitating tumor-targeted antibody production and inducing photodynamic cell death. CAPRN achieves tumor-specific accumulation via pH-responsive PEG detachment, enabling efficient intracellular gene delivery encoding anti-PD-L1 antibody. Laser-induced photodynamic therapy (PDT) not only triggers cancer cell death but also facilitates targeted antibody release from dying tumor cells. CAPRN demonstrates significant anti-tumor efficacy, attributed to multiple effects including enhanced antibody release, dendritic cell (DC) maturation, and T cell activation. Moreover, CAPRN exhibits substantial tumor suppression in both primary and bilateral tumor models, accompanied by activated T cell infiltration and enhanced immune responses. This study presents a novel strategy for priming robust immunotherapy, offering targeted antibody release through laser-assisted photodynamic nanoparticles.