The main aim of the study was to evaluate the chemopreventive potential of Kayan Karpam (KK) against Benzo(a) Pyrene (B(a)P) induced lung carcinogenesis in experimental mice. In this study, we evaluated the impact of KK as an effective antioxidant and anticarcinogenic agent against B(a)P, a possible carcinogen present in cigarette smoke. All mice were randomly assorted into five groups. Group I mice served as control (Control), group II mice were received KK at the dosage of 250mg/kg b.wt. for 16 weeks. Groups III-VI received B(a)P at the dosage of 50mg/kg b.wt. weekly twice orally for the first 4 weeks. Further, along with B(a)P, group IV received KK, as like group 2 for 16 weeks, group V mice received B(a)P, as like groups 3 and 4, along with KK starting from the 9th week of the experimental period. We observed, that carcinogen induced mice treated with different treatment regimens of KK showed a potent chemopreventive action. Significant (P<0.05) increases in cellular enzymatic antioxidants such as SOD, CAT and GPx and levels of non-enzymatic antioxidants like GSH, vitamins E and C were noted in KK treated mice. Highly significant reductions were observed in the levels of lipid peroxidative by products and lung cancer marker enzymes like AHH, ᵧ-GT, 5’-ND and LDH in the mice administered with KK. Supplementation with KK to tumor bearing mice normalized the expression patterns of pro- and anti- apoptotic proteins (p21, Bax, Bcl-2), modulated NF-κB, and reduced the levels of COX-2. These findings further suggest the view that the Indian medicinal plants present in KK are promising sources of potential drugs against lung cancer.