Objectives This study was performed to compare responses of Korean to the Sasang Constitution questionnaire with those of Japanese and to learn difference in characteristic according to the Sasang Constitution between two countries. Methods 301 Korean visiting the department of the Sasang Constitution, Dong-Eui Medical Center in Busan, Korea from November 2006 to September 2010 responded to the SSCQ-P(Sasang Constitution Questionnaire for Patients). Sasang Constitution specialist interviewed subjects and diagnosed their Sasang Constitution. 361 Japanese visiting the center for Kampo Medicine, Keio University in Tokyo, Japan from January 2010 to February 2011 responded the SSCQ-J(Sasang Constitution Questionnaire for Japanese). The Sasang Constitution was diagnosed in the same way as Korean. We compare responses to the SSCQ-P in Korean with those to the SSCQ-J in Japanese. Results 1. Among Soyangin related 58 items of Sasang Constitution questionnaire, 26, 46.36% items had statistically significant response results in both Korean and Japanese and response disposition of all these items was same. Among Taeeumin related 68items, 36, 52.94% items had statistically significant response results in both Korean and Japanese. Of these, response disposition of 35 items was same and that of 1 item was different. Among Soeumin related 71 items, 31, 43.66% items had statistically significant response results in both Korean and Japanese. Of these, response disposition of 28 items was same and that of 3 items was different. 2. The proportion of items having statistical significance and same disposition in both Korean and Japanese by Sasang Constitutional characteristic category[Features and Way of Speaking, Physical Appearance, Temperament and Talent, Pathological Syndromes] was as follows; In Soyangin, the proportion in Pathological Syndromes was 27.8% and that in the others was more than 41.7%. In Taeeumin, the proportion in Pathological Syndromes was 33.3% and that in the others was more than 57.9%. In Soeumin, the proportion in Features and Way of Speaking was 70.6%, that in Physical Appearance was 8.3% and that in the others was 30~40%. Conclusions The response disposition of many of items having statistical significance between Korean and Japanese was same and that of a few was different. From this, there are many common Sasang Constitutional characteristics between two countries, and possibility of applying the Sasang Constitutional Medicine of Korea to Japan.