Developing countries are now witnessing an increase in overweight; obesity and obesity-related morbidity. We determined the prevalence of obesity using the measure of body mass index (BMI) and hypertension and the association between obesity and hypertension among adults in Ogbomoso, Nigeria. A cross-sectional descriptive study of 400 adults was carried out. Participants were administered a standardized questionnaire and had measurements of weight, height and blood pressure taken. Four hundred subjects were randomly selected (221 females and 179 males) with a mean age of 48.65 ± 16.56 years. The overall prevalence of obesity was 14.75% (8.9% for males and 19.5% for females). In addition, 62.4% of the females were sedentary as compared to 50.8% of the males and the difference is statistically significant. The families of most of the subjects who were obese (88.1%) preferred high calorie diets. The prevalence of hypertension among the study population was 50.5% [49.3% for female and 52.0% for males (p>0.05)]. The prevalence of hypertension among the subjects who were obese was 72.9%. Obesity in this environment is particularly significant among females and is associated with hypertension, physical inactivity and the consumption of high calorie diets.