To evaluate the costs of the hypertension screening program of the Korea Medical Insurance Corporation, the records of the screening examinations were used. The sample size was 49,983 of the 906,554 people insured by the Corporation and was obtained by two-stage stratification random sampling. The alternatives for efficiency of the screening program, which were divided into three categories : modification of the screening test package, application of other hypertension diagnostic criteria, and selective approach of tested groups by age, were evaluated according to the cost per patient detected. The results of this study were as follows In the hypertension screening system, the cost per patient detected was Won 30,883. The most nonsensitive test for hypertension detection was ophthalmoscopy, which was examined during the second stage of screening. If the ophthalmoscope examination was excluded, olny one person was not detected, which was 0.2% of detected persons, and the cost per patient detected decreased to Won 28,098. The most efficient modification of the screening test package was measurement of blood pressure through the first and second stages of screening. The cost per patient detected by this modification was Won 24,408. The application of other diagnostic critera, which were more restricted criteria, increased the cost per patient detected by 3.7%-6.7%. The cost per patient detected were Won 170,582 for persons less than 39 years old, Won 20,032 for persons 40 to 59 years old, and Won 8,675 for persons 60 years old and over. In conclusion, the best alternative suggested with respect to efficiency and practical application excluded the ophthalmoscope examination of second stage screening and restricted the target population to persons greater than 40 years old. The application of this alternative decreased 54.9% of the screening costs and the cost per patient detected was Won 15,222. This study was limited in that measurement of effectivenes was not of the ultimate goal of screening, which is decreasing morbidity and mortality, but was of disease detection as the short-term objective.