The article presents results obtained in study of relationship between polymorph variants of CYP1A1 and CYP1A2 genes with reproductive and thyroid diseases risk in female workers of petrochemical industry, when compared with reference group females. Variants TD and DD of CYP1A2 gene appeared to be associated with nodes formation in uterus and breast in female workers and reference group females. Following liability markers are obtained: homozygous in rare allele genotype CC of CYP1A1 gene for reproductive and thyroid diseaes (fibrous cystic mastopathy and nodular goitre), heterozygous genotype AG of CYP1A1 gene in uterine myoma and fibrous cystic mastopathy, homozygous in deleted T genotype of CYP1A2 gene in autoimmune thyroiditis. Occupational hazards and long length of service at hazardous industries increase effects of rare alleles of the genes studied.