Purpose: The purpose of this study was to assess the effectiveness of a community based group validation therapy program developed to promote positive behavioral and emotional outcomes in community-dwelling Korean patients with dementia. Methods: A nonequivalent control group pretest-posttest design was used to measure the effects of the program on the behavior and emotions of patients with dementia. Participants in a validation therapy program were 33 patients who attended 10 weekly sessions of approximately 50 minutes each. Effects were evaluated through pre and post tests that included measurement of depression (SGDS-K), quality of life (GQOL-D), behavioral problems (NPI-Q), and cognitive function (MMSE-KC). The study variables were analyzed using x2-test and t-test with the SPSS statistical package. Results: For the participants, a statistically significant reduction in depression and behavioral problems was found, as well as a significant increase in quality of life. However, no significant changes in cognitive function were revealed. Conclusion: Findings indicate that validation therapy reduces symptoms of depression and behavioral problems in older adults with dementia. It, therefore, can be considered as a program to improve quality of life in this population.