We investigated the influences of 'Circumstance Insensibility', 'Unsafe Driving', 'Incautious Driving', and 'Self-efficacy of Driving', consisting of driving confidence level, on traffic accidents. 1055 drivers conducted Driving Confidence Level Questionnaire, items about their dangerous driving experience and traffic accidents. Among them, after checking the missing items, we analyzed data of 998 drivers. As a result, we found the relation between driving confidence levels and traffic accidents. Specially, 'Circumstance Insensibility' and 'Unsafe Driving' influenced traffic accidents. However 'Circumstance Insensibility' had negative effects, the other side 'Unsafe Driving' had positive effects on traffic accidents. This result means each factor of driving confidence levels have different relation with traffic accidents. 'Incautious Driving' and 'Self-efficacy of Driving' didn't have any effects on traffic accidents in this research. In future, it should be investigated 'Incautious Driving' and 'Self-efficacy of Driving'.