In this study, we sought to fabricate a type of anti-HER2 ICG-DOX-encapsulated polyethylene glycol (PEG)-poly(lactic-co-glycolic acid) (PLGA) diblock (PEG-b-PLGA) copolymeric nanoparticles (HIDPPNPs) to explore the co-administration of photochemotherapy and target-specific treatment for HER2-overexpressing breast cancer cells. The gene discussed is ERBB2; the disease is breast carcinoma.