OBJECTIVES: To describe health behaviors related to hypertension in rural population of Korea and focused to identify inappropriate awareness, treatment, and control of hypertension. METHODS: We surveyed 5,517 adults (2,288 males, 3,229 females) older than 30 years in 58 rural areas, purposely sampled nationwide from December 1996 to February 1997. Blood pressure was checked twice at the time of the first visit. For those who showed high blood pressure using the JNC-6 criteria at their initial visit, we followed up their blood pressure one week later. Also information on the health behavior related to hypertension was collected through the person-to-person interview using structured questionnaire at the first visit. RESULTS: For the past one year, females had more experiences of checking their blood pressure than males (77.3% versus 69.5%, p=0.001). Through the results of consecutively checked blood pressure, only 51.7% of the hypertensives were aware of their condition. Of the hypertensives who aware of their condition, 44.4% did not receive any medication and/or recommendation. And 50.4% of the hypertensives who had anti-hypertensive medication were classified as still having hypertensive blood pressure by 160/95 mmHg criteria. Of the medicated, 54.8% were found to take medication regularly for the past six months. Among the medicated, only 11.4% knew the name of anti-hypertensive drug they had. CONCLUSIONS: 'Rule of halves', which works in the situation of no special efforts for hypertension control, was identified. This study showed that much efforts to control hypertension would be required in the rural population of Korea.