ABSTRACT Purpose Sitting Baduanjin exercises can be effective in treating mild cognitive impairment (MCI). However, evidence on effectiveness of sitting Baduanjin exercises is lacking. This study investigated the effects of sitting Baduanjin exercises on cognitive function, attention, and muscle strength in patients with MCI. Design Quasi-experimental. Methods The participants were assigned to the experimental (n = 12) or comparison group (n = 12). The experimental group performed sitting Baduanjin exercises three times weekly for 40–50 minutes per session for 12 weeks, while the comparison group maintained their usual routine and attended health-related education. The two groups’ cognitive function and attention were assessed through a questionnaire and their muscle strength was measured at weeks 0, 9, and 13. Findings The experimental group showed significant improvements in cognitive function, attention, and muscle strength in the right shoulder anterior flexor; however, the left shoulder anterior flexor group showed no obvious improvements. Conclusion Sitting Baduanjin exercises feature simple actions, are convenient, and have positive effects on improving cognitive function, attention, and muscle strength in patients with MCI. Clinical evidence Baduanjin exercises are suitable for long-term community frontline care services. Early intervention with this exercise program may prevent healthy older people or those with health issues from progressing to dementia.