Research shows the benefits of mentoring in promoting positive youth development. Yet less is known about mentors and what predicts mentor satisfaction. Such knowledge is vital to understanding how to recruit and retain adult mentors for youth. Thus, in the current study, we examine mentors as embedded in a social ecology of relationships, such as relationships with their mentee, mentee's family, and mentoring organization they volunteer with. We use data from 247 mentors to test how each of these relationships (mentor with the mentee, mentee's family, and mentoring organization) independently and interactively predict mentor satisfaction. Findings indicate that all relationships are unique predictors of mentor satisfaction, and that relationships with the mentee's family and mentors’ mentoring organization interact in predicting mentor satisfaction. Overall, considering multiple relationships shows how various dimensions of the social ecology uniquely and interactively predict mentor satisfaction. Limitations and implications for mentoring practice are discussed.