The proof‐of‐concept experiments which are executed on an orthotopic liver cancer model have verified that intratumoral SSN‐medicated piezoelectrocatalytically generated H2 liberates effector CD8+ T cells from the immunosuppression of tumor cells through down‐regulating PD‐L1 over‐expression, and simultaneous LA deprivation activates CD8+ T cells by inhibiting regulatory T cells, efficiently co‐activating tumor immunity and achieving a high outcome of liver tumor therapy with complete tumor eradication and 100% mice survival. The gene discussed is CD274; the disease is liver cancer.