Health promotion activities to educate the public about health lifestyles have been performed widely in industrialized countries where chronic adult diseases have become prevalent. According to a basic principle of health promotion activities, the symptoms of many diseases are regarded as the result of inadequate health behavior, curable by modifying health behavior. It is thus possible that an exposure to health promotion activities might instill negative attitudes towards organ transplants, because program participants may conclude that persons who need an organ transplant have become unhealthy as the result of their own poor health habits. In this study, two types of surveys were undertaken to test this hypothesis. The subjects of the first cross-sectional study were 712 male and female Japanese citizens, and those of the second case-control study were 240 female company employees in Japan. In the first study, a logistic regression analysis was used and the following findings were obtained. (1) Compared with the persons who felt that they did not have enough practical knowledge about individual health practices, those who felt that they had adequate knowledge were 0.66 times less likely to support organ transplants. (2) Compared with those who were not willing to spend money on healthful things, the persons who were willing to do so were 0.51 times less likely to support organ transplants. In the second case-control study, it was revealed that the subjects who had negative attitudes towards organ transplants had consistently healthier lifestyles than did those who had positive attitudes towards organ transplants. Based upon the present findings and the nature of the basic principles of health promotion activities, we infer that community health promotion activities have a negative influence upon citizens' opinions of organ transplants. Since these findings have health policy implications, more studies are necessary to conclusively evaluate the effects of health promotion activities upon attitudes toward organ transplants.