Objective: To assess self-management behaviors and service needs among older adults with diabetes in Guojicun Community, Yuzhong District, Chongqing, and to provide empirical evidence for improving community-based diabetes care. Methods: A cross-sectional survey was conducted among eligible older community-dwelling adults with diabetes. Data were collected using a standardized self-management scale and a service-needs questionnaire, and analyzed descriptively with supply-demand matching. Results: Overall self-management was low to moderate and uneven across domains. Medication adherence and fruit and vegetable intake were relatively better, whereas exercise, prescribed blood glucose monitoring, and foot care remained weak. Patients reported substantial needs for home-based glucose monitoring and complication prevention, whereas community service coverage remained limited; psychological support was particularly underprovided. Health education relied mainly on offline lectures, with predominantly one-way delivery and limited interaction or individualized feedback. Conclusion: Older adults with diabetes in this community had relatively weak self-management capacity, and current service provision was structurally misaligned with actual needs. Primary care should adopt assessment-based, stratified interventions, prioritize home monitoring and psychological support, improve interactive and context-sensitive health education, and integrate family, community and policy resources to strengthen chronic disease management.