This study used a quasi-experimental single-group time series design to compare the effects of a physical activity and brain exercise program on the cognitive ability of healthy Thai elders. It was conducted from December 2015 to May 2016. A purposive sample of 23 people of over 60 years of age was used. The research instruments consisted of 1) the Mini-Mental State Examination Thai 2002 (MMSE-Thai 2002), 2) the Montreal Cognitive Assessment (MoCA, Thai version), and 3) the physical activity and brain exercise program devised for this research. The program components were validated and reviewed by 3 experts and yielded a content validity index (CVI) of 0.96. Participants attended the program 8 times (3 h each) over 5 consecutive weeks. Subsequently, participant follow-up progress reviews were done in weeks 10, 14, and 18. Data were analyzed using descriptive statistics and ANOVA with Wilcoxon matched-pairs signed-rank test and repeated measures ANOVA. Results revealed that the average score for cognitive ability (Mental State and cognitive function) in weeks 10 and 14 and at follow-up in week 18 were statistically significantly higher (p < .05) than the baseline. Recommendation: the physical activity and brain exercise program could improve cognitive ability and should be included in health promoting activities in elders’ clubs or senior schools in the future.