The study problem was to determine the reliability of the Stewart pain circle measurement tool with Korean subjects. The purpose was to assess the tool for potential use in research in Korea. The subjects were 95 primary school students and 103 university students in Seoul. The study was conducted from May to June 1990, using Stewart's pain color circle tool. To determine the difference in the rated intensity of the order of the pain color circles, statistical mean and standard deviation were employed. Item reliability and test-retest reliability were used to test for reliability. ANOVA and t-test were used to explore for differences in the rated intensity of the order of the pain color circles according to the subjects' general characteristics. The findings were as follows ; 1. Higher level pain intensity was assigned to color circle numbers 2, 4, and 6(These contain large amounts of color). Lower level pain intensity was assigned to numbers 1, 3. and 5(These contain small amounts of color). Higher and lower levels of pain intensity selection patterns were the same as Stewart' s but the highest rating of pain was different. The highest pain intensity rating was given to the color red in this study instead of black as in Stewart's test. 2. University students and primary school studetns' ratings were not very diftefeient. 3. Pain color circle reliability was x=0.3468, Test-retest reliability was supported(t=0.02-0. 97, p=0.337~0.988). 4. Differences in the rating of the pain intensity order were related to the supjects' age and sex, but not to religion. It was concluded that the pain color circle measurement tool is worth for further study as a research instrument with both Korean adult and child clients for validity and reliability.