Purpose: The purpose of this study was to identify the association between Sasang constitution and type A/B personality. Method: The subjects for this study were 113 Korean adults living in Kangwon Province, the northeastern part of Korea. The data were collected from March 10 to April 13. 2002 using a structured questionnaire. The instrument for this study were QCSSII (Questionnaire for Sasang Constitution Clsssification II) by Kim et al.(1996), and the Revised Type A/B personality by Eysenck & Fulker(1983). The data were analyzed through the SPSS 10.0 for Windows program using frequency, percentage, $x^2$-test, ANOVA, and Pearson correlation coefficient. Results: The results of the study are as follows : 1. Of 113 Korean adults, the portion who were Taieum-in, Soeum-in, Soyang-in was 39.8%, 34.5%, 25.7% respectively. 2. For type A/B personality, mixed type was most common, 19.4% of the participants were of type B and 8.0%., type A. 3. For type A/B behavior, mixed type was most common at 47.8% and type A was 2.7%. 4. There were statistically significant differences in the Sasang constitutional type according to BMI (F=14.542, P<.001), and alcohol consumption (F=4.256, p<.018). 5. There were significant difference between type A/B Personality and BMI (F=3.592, P<.032). 6. The data shows correlations between BMI and amount smoked per day (r=2.74, P<.004), between BMI and alcohol consumption (r=-.303, p<.008), between BMI and Sasang constitutional type (r= -.592, p<.0001), between BMI and type A/B personality (r=285, p<.011), between amount smoked per day and alcohol consumption (r= .-361, p<.001). between alcohol consumption and Sasang constitutional type (r=-.306, p<.019). between perceived health state and type A/A personality (r= .246, p<.011). Conclusion: According to the above findings, it can be concluded that further research is need to understand the Sasang constitution for the discipline of Nursing and for nurses to prepare nursing protocols relevant to Sasang constitutional care. Also, Sasang constitution has to be considered in research and practice in the health care delivery system.