This is a community-based population survey carried out by the Yang-Ming Crusade to investigate the impact of years since menopause on the development of glucose intolerance in post-menopausal women. A total of 5412 women were screened with fasting plasma glucose. Those with fasting plasma glucose levels between 5.5 and 7.8 mM were given an oral glucose tolerance test. Among the 5412 women screened, 2039 (37.7%) were post-menopausal with a median age at menopause of 49 years. Pre-menopausal women showed impaired glucose tolerance (IGT) and diabetes mellitus (DM) prevalences of 3.7% and 3.1% respectively, whereas the corresponding figures for post-menopausal women were 8.4% and 17.6%, respectively. Comparing DM versus normal glucose tolerance (NGT) and IGT versus NGT as dependent variables in logistic regression analysis, menopause status was significantly associated with DM and IGT. In post-menopausal women, after maintaining body mass index, waist-hip ratio, systolic blood pressure, diastolic blood pressure, family history of DM, age at menopause, cholesterol, high density lipoprotein cholesterol and triglycerides as controls, years since menopause was the only significant factor associated with IGT (OR = 1.05, 95%CI 1.01-1.08) and years since menopause was not associated with DM. Further analysis indicated years since menopause (OR = 1.06, 95%CI, 1.01-1.11) was the only factor significantly associated with IGT for women whose age at menopause was greater than 49 years. Our study indicates that in subjects who have not undergone hormone replacement therapy and whose age at menopause is greater than 49 years, an increase in years since menopause confers a negative influence on glucose tolerance and increases the risk of IGT by 6% for each year after menopause.