Background: Gender is known to be one of the factors linked to differences in cardiovascular morbidity and mortality. However, little information is available regarding gender differences in the risk factors for intracranial cerebral atherosclerosis (ICAS). Objective: This study investigated the risk factors for ICAS separately by gender in an asymptomatic population. Methods: We collected data from a consecutive series of 935 subjects who had no history of stroke and who had undergone transcranial Doppler ultrasonography (TCD). For each subject, their medical history was documented and tests for biochemical markers were performed. Multiple logistic regression analyses were separately conducted to assess the risk factors associated with ICAS by gender. Results: The risk factors for asymptomatic ICAS were determined for every 10-year increase in age (odds ratio [OR] = 1.74, 95% confidence interval [CI] = 1.23-2.46), diabetes mellitus (DM) (OR = 3.45, 95% Cl = 1.49-7.95), smoking (OR = 2.09, 95% CI = 1.01-4.32), and hypercholesterolemia (OR = 3.31, 95% CI = 1.15-9.50) for male subjects; risk factors female subjects included hypertension (OR = 2.10, 95% CI = 1.40-3.15) and DM (OR = 2.45, 95% CI = 1.11-5.44). An additional stratified analysis indicated that there was no significant risk factor for male subjects aged <50 years, whereas hypertension (OR = 2.90, 95% CI = 1.57-5.37) was the significant risk factor for female subjects aged <50 years. For male subjects aged 50 years, DM (OR = 6.00, 95% CI = 1.87-19.20), hypercholesterolemia (OR = 4.72, 95% CI = 1.05-21.19), and every 10-year increase in age (OR = 4.33, 95% CI = 2.02-9.28) were significant risk factors for asymptomatic ICAS, whereas DM (OR = 2.93, 95% CI = 1.14-7.48) was significant for female subjects aged years. Conclusions: The findings suggest that the risk factors for asymptomatic ICAS differ between sexes, indicating a possible role of sex hormones in the development of ICAS. (Gend Med. 2011;8:14-22) (C) 2011 Elsevier HS Journals, Inc. All rights reserved.