Cooperative enterprises have great potential and contribution to the economic and social development of a country. The sustainability of cooperative enterprises depends on their members as the owner and the user of cooperative services. The engagement of members in cooperative activities helps to enhance the effective performance of the cooperatives. Achieving a sustainable level of engagement is a difficult challenge. One of the important stimulants of engagement is the leadership factor. In a cooperative enterprise, the leaders are elected by the members at the cooperative's annual meeting. This study aims to know the effect of servant leadership on member engagement with psychological capital as mediating variable using the Structural Equation Modeling (SEM). A questionnaire survey with a 1-6 Likert scale is executed to achieve the objective of the study. Respondents of this study consist of 224 members of the civil servant cooperatives located in the Agam Regency, Indonesia. The result from the study revealed that servant leadership has a positive impact on member engagement. The study also shows that psychological capital mediates the relationship between servant leadership and member engagement. This study's findings provide an expanded understanding of the antecedents of member engagement and they will be useful for cooperatives in engaging their members and optimizing their performance to contribute to the improvement of community well-being. © 2023 Author(s).