Obesity and smoking are the two modifiable risk factors that contribute the most for many chronic diseases. Obesity has nearly doubled in Oklahoma and in the US since 1990 while Oklahoma adult smoking rates have remained above 25%. The purpose of this study was to utilize the Behavioral Risk Factor Surveillance System (BRFSS) to describe the associations between overweight, obesity, and cigarette smoking with selected chronic diseases among Oklahoma adults. The BRFSS is an ongoing, state-based, random-digit dialing telephone survey of the non-institutionalized adult population ages 18 years and older designed to collect various kinds of health-related information. Descriptive statistics were obtained for high blood pressure, high cholesterol, diabetes, asthma, and arthritis by BMI status (i.e. not overweight, overweight, obese) and smoking status (i.e., current, former, never). Logistic regression was performed to test for associations between BMI status or smoking status and these diseases. Self-reported diabetes, arthritis, and lifetime high blood pressure and high cholesterol rates were higher among those who were overweight and highest among those who were obese, while asthma rates were higher among obese adults than those who were not obese. Asthma rates were higher for those who currently smoke than former smokers and never smokers. Former smokers had significantly higher rates of high blood pressure, high cholesterol, diabetes, and arthritis compared to never smokers or current smokers.