This study aims to understand volunteer motivations of older adults and their self-efficacy. By analyzing the influence of volunteer motivations on self-efficacy, this study will recommend apply strategies of volunteers and ways to improve self-efficacy. By 2017, 363 active aging learning centers (AALCs) have been established. At the same time, older adults were also encouraged to join volunteer services and became important human resource to assist the operation of the centers. However, what motivates older adults to participate in volunteer service, how to improve volunteer effectiveness and how to promote the continued participation of volunteers are the focuses of this study. This study used a questionnaire survey, which included: personal background variables, participation motivation scale, and self-efficacy scale. The subjects were volunteers of the AALCs. From the 316 centers set up in 2014, 60 centers were selected according to the principle of proportionality. There were 20 questionnaires being sent to each center, 1200 in total, and the valid response rate was 75.58%. This study conducted statistical analysis with descriptive statistics and regression analysis. Five conclusions were obtained, including: 1 The volunteers have a high degree of motivation for participation, among which the mean of self-growth is the highest, followed by values identification, and the third is interpersonal interaction. 2 The volunteers have a high degree of self-efficacy. Among them, the mean of worldly-wise is the highest, followed by adaptability to change, and third, self-awareness. 3 The higher the motivation for volunteers, the higher their overall self-efficacy 4 Volunteers who are motivated by social services have higher overall self-efficacy, and service confidence. 5 Volunteers who are motivated by values identification have higher self-awareness, worldly-wise and adaptability to change.