As a nonpharmacological method for cognitive rehabilitation, older adults with mild cognitive impairment (MCI) may benefit from Baduanjin exercise (BE), a moderate-intensity aerobic exercise. This meta-analysis was conducted to determine if BE is effective in enhancing cognitive performance in older adults with MCI. Using a combination of topic phrases and free words, systematic searches were executed in nine databases. Review Manager 5.4 was used to retrieve and statistically evaluate the data. Fourteen randomized controlled studies comprising 994 individuals aged ≥60 years were included in the meta-analysis. BE enhanced the general cognitive performance in individuals with MCI as measured by the Montreal Cognitive Assessment (standardized mean difference [SMD] = 2.56; 95% confidence interval [CI], 2.17, 2.96; p < 0.001). The level of memory decline (Wechsler Memory Scale; SMD = 12.46; 95% CI, 8.36, 16.57; p < 0.001), executive function (Trail Making Test; SMD = -7.08; 95% CI, -11.21, -2.94; p < 0.001), and frailty (Edmonton Frailty Scale; SMD = -0.97; 95% CI, -1.30, -0.64; p < 0.001) were all improved with BE for older adults with MCI. This study presented a therapeutic practice guide for using BE for cognitive rehabilitation in older adults. BE notably improves cognitive function in older adults with MCI and can be an excellent nonpharmaceutical therapy option.