Background and Purpose— Although serum γ-glutamyltranspeptidase (GGT) levels have been associated with cardiovascular disease incidence, few studies have taken into account the effect of alcohol intake on GGT levels. In this study, we examined the relationship between GGT and stroke incidence according to drinking status. Methods— We conducted a prospective cohort study of Japanese women (N=6281) and men (N=3471) aged 40 to 69 years living in communities under systematic surveillance for stroke incidence. Results— During the 18-year follow-up, 202 (3.2%) women and 230 (6.6%) men had strokes. Serum GGT levels were positively associated with risk of total stroke for women but not men. The multivariable hazard ratios of total stroke for the highest quartile of GGT compared with the lowest quartile were 1.56 (95% CI, 1.01 to 2.39) for women and 1.37 (95% CI, 0.89 to 2.11) for men. Moreover, GGT was associated with total and ischemic stroke risks for never-drinking women. Conclusions— Serum GGT is associated with risk of total and ischemic strokes for Japanese women, especially never-drinkers.