The purpose of this study is to clarify the characteristics of “vicarious experiences” that enhance the self-efficacy of nursing students in practice of adult nursing. A questionnaire survey was conducted on 69 students who completed the practice of adult nursing at Faculty of Nursing, A University. As a result, four factors were extracted from the "vicarious experiences". They are 1 “relationship with respected patients", 2 “development of nursing by other students", 3 "education of patients toward reorganization of life" and 4 "nursing practice by certified nurses". It is found that the first three factors are directly related to self-efficacy, while the last factor, which nursing students rarely experience on their behalf, is also intimately related to self-efficacy, but in a different way.