Background: Early initiation of bystander cardiopulmonary resuscitation (CPR) improves the chances of successful resuscitation and survival. The aim of the present study was to identify the attitudes of Japanese subjects toward bystander CPR and to compare them with those observed in previous studies in 1998 and 2006. Methods and Results: Participants were asked about their willingness to perform CPR in 5 different scenarios and their willingness to perform chest compression (CC) plus mouth-to-mouth ventilation (MMV) versus CC alone. A total of 2,785 individuals completed the questionnaire, including high school students, teachers, medical nurses, and medical students, whose characteristics were not statistically different from those in the previous studies. Only 15-30% of participants were likely to perform CC plus MMV, especially on a stranger or a trauma victim; these percentages in nurses and medical students were significantly lower than those in the previous studies. But 50-100% of them were likely to perform CC alone, consistent with the results obtained in 2006. The reasons for the unwillingness among laypeople to perform CC plus MMV were inadequate knowledge and/or doubt regarding whether they could perform the techniques effectively, while health-care providers reported a fear of disease transmission. Conclusions: Most participants are unlikely to perform CC plus MMV, especially on a stranger or trauma victim, but are more likely to perform CC alone, as also found in the previous studies. (Circ J 2012; 76: 1130-1135)