The purpose of this study was to explore the relations between lifestyle factors and blood pressure (BP) control among patients with hypertension who were regularly taking antihypertensive medication as prescribed. From the 2005 Korean National Health and Nutrition Examination Survey data, the 690 individuals diagnosed with hypertension who were regularly taking antihypertensive medication were identified. Slightly more than half of the patients (54.3%) had their BP under control. Younger patients, those having one or more comorbidities and those performing physical activity at least 4 days a week were more likely to have their BP under control, while overweight patients, heavy alcohol drinkers, and those with mild to very severe stress had lower rates of BP control. The study results suggested that to reduce uncontrolled BP, public health efforts should target old and overweight patients and those with unhealthy lifestyles including heavy alcohol drinking, stress, and lack of physical activity.