This study aims to evaluate the effectiveness of adaptive computerized cognitive training (CCT) in improving cognitive function among community-dwelling older adults with mild cognitive impairment (MCI) and to compare the maintenance effects of different training frequencies after the initial intervention. A quasi-experimental study will be conducted in three communities in Shenyang, Liaoning Province, China. All participants will receive a 12-week adaptive CCT program. Participants will be assigned to either a high-frequency maintenance training group or a training discontinuation group. Cognitive assessments will be performed at baseline, immediately after the intervention, and during follow-up. The primary outcome is global cognitive function, while secondary outcomes include memory, attention, executive function, language, visuospatial ability, and activities of daily living. The findings of this study are expected to provide evidence for optimizing computerized cognitive training programs and long-term management strategies for older adults with MCI in community settings.