Colorectal cancer is caused by both genetic and environmental factors. We investigated the association between polymorphism of cytochrome P4501A1 (m2) and colorectal cancer in 40 cases and 20 controls using PCR-RFLP. Our results showed that a statistically significant association existed between CYP1A1 variant genotype (p=0.015 and the odds ratio OR =0.105 with the 95% confidence interval 0.028- 0.390) and colorectal cancer.