It has been proposed that high levels of galactose consumption increase the risk of ovarian cancer. Galactose levels are determined, in part, by the galactose-1-phosphate uridyl transferase gene (GALT). The N314D allele of the GALT gene has been associated with low GALT activity and with an increased risk of ovarian cancer. We screened for the presence of the N314D GALT allele in 891 incident cases of epithelial ovarian cancer and in 364 unaffected female controls. No significant difference in the prevalence of the N314D allele was observed between the cases (18.1%) and the controls (18.7%). The odds ratio associated with the presence of one N314D allele was 0.94 (95% confidence interval (CI), 0.68-1.3; P = 0.70), and the odds ratio associated with two N314D alleles was 1.62 (95% CI, 0.34-7.7; P = 0.54). Subanalyses of the cases by histological type, by age, by ethnic group, by family history, and by BRCA1/2 mutation status did not reveal any significant associations. We conclude that the GALT N314D allele does not predispose to epithelial ovarian cancer.