Abstract: In recent years, considerable emphasis has been focused on identifying new cancer chemopreventive agents, which could be useful for the human population. The present study was aimed to investigate effect of crocetin on Xenobiotic enzymes and glutathione metabolizing enzymes in Benzo(a)pyrene (B(a)p) induced lung cancer in Swiss albino mice. The lung cancer bearing mice shows elevated level of Phase I enzymes (cytochrome P450, cytochrome b5 and NADPH cyto.C reductase), glutathione-metabolizing enzymes (glutathione peroxidase, glutathione reductase and glucose-6-phosphoate dehydrogenase) and decreased level of Phase II enzymes (UDP-glucuronyl transferase, glutathione S-transferase, quinone reductase). Oral administration of crocetin (50 mg kg-1 body weight) to B(a)p administered animals altered the enzymes level near to normal during initiation and post-initiation treatment. Based on the results, our finding suggests that crocetin have protective role against B(a)P induced lung carcinogenesis.