Objective: We examined the association between older adults' mealtime interactions at senior centers in Shanghai and their life satisfaction. Competing hypotheses, derived from socioemotional selectivity theory and activity theory, were tested. Method: Data were obtained from the 2011 Shanghai senior center service utilization survey (N = 320). Relationships between respondents' mealtime interactions and life satisfaction were tested using multilevel regression modeling. Results: After adjusting for demographics, interactions with tablemates (companionship, self-disclosure, and instrumental support) were positively associated with respondents' life satisfaction. These associations varied by senior centers. However, the number of tablemates was not significantly associated with respondents' life satisfaction. Discussion: Findings support the activity-theory-based hypothesis that mealtime interactions are related to older adults' life satisfaction independent of the number of tablemates. This study illuminates the value of social interactions in the context of community dining programs for the rapidly increasing older population in urban China.