The catechol-O-methyltransferase (COMT) gene encodes enzymes that inactivate catechol estrogens and may have a protective role in estrogen-induced tumorigenesis, such as uterine leiomyoma (fibroids). Val158Met is a common single-nucleotide polymorphism of the COMT gene (Ex4-12 G>A; rs4680) that results in a lower activity enzyme, increasing susceptibility to tumorigenesis. The purpose of this study was to evaluate the relation between the COMTVal158Met polymorphism and uterine fibroids. Participants were 972 premenopausal African American (n = 576) and white (n = 396) women from a cross-sectional sample of women in the National Institute of Environmental Health Science's Uterine Fibroid Study. Blood was collected from participants for DNA, and telephone interviews and questionnaires were completed to gather demographic and reproductive history. Prevalence ratios and 95% confidence intervals were estimated using race-specific log-risk regression models. Effect measure modification by age, body mass index, oral contraceptive use, full-term births, smoking, and alcohol use were also evaluated. Distributions of genotypes and fibroid prevalence varied by race. No associations between fibroids and Val158Met were observed among African American or white participants. This study suggests that variation in this polymorphism alone does not affect fibroid prevalence. Additional research is needed to examine other variations and haplotypes within the COMT gene.