Background The risk of cognitive decline in older adults makes it necessary to design training programs for the improvement of cognition. Aims To determine the efficacy of applying a combined program of computerized cognitive training (CCT) and mindfulness for improving cognition and mood and quality of life in people aged 60 years and older, compared with using both interventions separately. Methods Adults, older than 95 years were assigned to groups that subsequently received one of the three interventions (CCT, mindfulness, and combined). Cognitive, emotional, and quality of life assessment instruments were administered pre- and post-intervention. The standardized individual change was determined, and one-factor ANOVAs and ANCOVAs were conducted to test between-group differences. Results After controlling for confounding factors, greater significant improvements were obtained in the combined group compared with the CCT and mindfulness groups in selective attention (median effect size) and abstract reasoning (large effect size). No significant differences were found in the rest of cognitive variables, mood or quality of life. Conclusion The findings indicate that, with the same investment of time, combining CCT and mindfulness effectively improves selective attention and abstract reasoning, in older adults. This combination of strategies might have implications for the improvement of cognitive impairment in older adults.