Pulmonary cancer confronts the greatest hurdle of resistance against most chemotherapeutic drugs. This may be circumvented with a combination of conventional chemotherapy with bioactive herbal adjuvant. Epigallocatechin‐3‐gallate (EGCG), was investigated for its chemo‐sensitizing property along with doxorubicin (Dox), in an intrinsically nonresponsive lung adenocarcinoma (LAC) cell line, A549. A compromised functionality of Dox was reversed when EGCG was used as an adjuvant. On one hand, Dox (10 μM)‐EGCG (0.5 μM) post treatment combination decreased the drug efflux, multidrug‐resistance (MDR) signaling, invasiveness while, on the other hand, it increased drug internalization, cell‐cycle arrest, stress‐induced damage, and finally cell death. The resistant nature of A549 was probably due to constitutive activation of nuclear erythroid 2‐related factor 2 (Nrf2) and its upstream/downstream antioxidant effectors, which were also pro‐oxidatively coordinated by EGCG. In conclusion low dose EGCG improved Dox‐toxicity and imparted oxidative damage‐mediated antineoplastic efficacy by reorienting the redox signaling in A549 LAC cells.