Medical ethics education program needs to be evaluated just like other education programs. After 3 years of medical ethics education, we studied the effect of it by a questionnaire and DIT test developed by Rest. The results of the questionnaire survey revealed that the students had supportive attitude in general on the educational program which is composed of dilemma discussion. In addition, the DIT test showed that both the higher p-value group and the lower p-value group in the pre-educational test shifted toward the mean p-value after the education. This implicates that medical ethics education practically lowered the p-value of pre-test higher group(statistically meaningful) and raised the p-value of the pre-test lower group(statistically not meaningful). The lowering effect for the pre-test higher group could be explained by the “realization effect” of the education program. We think that the influences of discussion leaders and the natural lowering trends reported by other researchers could contribute to the “realization effect”.