The Mediterranean diet has been recommended to delay cognitive decline, but adherence to the diet among older adults remain poor, and research on interventions that effectively promote the diet has been inconclusive. This study examined the effects of a mini-flipped, game-based Mediterranean diet learning program in improving dietary behavior and cognitive function in community-dwelling older adults in Taiwan. A cluster randomized controlled trial was conducted. The experimental group completed an 8-week, mini-flipped, game-based learning program. Data were collected at baseline and 8 weeks after intervention. Outcome measures included dietary behavior, global cognitive function, and subjective cognitive dysfunction. Compared with the control group, the experimental group exhibited significantly improved Mediterranean diet behavior and global cognitive function after the intervention, although there was no significant difference in subjective cognitive function. Future research should be conducted with larger populations and longer-term follow-up to evaluate the effect of this learning program.