Within the framework of an international collaborative network, we measured the prevalence of diabetes mellitus in a traditional Yoruba community in the city of Ibadan, Nigeria. Using a random sampling technique we enrolled a community sample of 247 men and women. Fasting blood glucose (FBG) was measured at the community clinic from a fingerstick using the Companion2 Medisense blood glucose meter. The mean FBG was 4.7 mmol/L and 4.9 mmol/L for men and women, respectively. Using the 1985 WHO criteria, the prevalence of diabetes was 2.8%. There was no significant rise in FBG with age. Compared to the lowest quartile of the body mass index (BMI), there was about a 1.5 fold increased risk of developing elevated FBG. The test of trend between FBG and BMI was however not statistically significant. Despite a modest hypertension rate (22.3%), there was no significant difference in the FBG for hypertensives compared to normotensives. The findings of this study show that the prevalence of diabetes mellitus in this West African community remains low compared to nations in Western societies. However, in comparison to previous estimates from sub-Saharan Africa, the prevalence of adult onset diabetes seems to be on the increase.