Objective: To assess the effects of Tai Chi (Chinese shadow boxing exercise) for improving the lower-limb muscle strength in elderly people. Methods: The PUBMED database (from 1950), EMBASE-ASP database (from 1974), Cochrane Library (from 1991), Elsevier sciences database (from 1990), OVID full text database (from 1997), Springer-link database (from 1997), The National Research Register database, ISI Web of knowledge (from 1963), Chinese Medical Citation Index/Chinese Medical Current Contents (CMCI/CMCC, from 1989), China Knowledge Resource Integrated Database (CNKI, from 1915),VIP database (from 1989), and Wanfang database (from 1977) have been searched only for the English and Chinese literatures updated to 10-30-2010. Two researchers independently assessed the methodological quality of studies, extracted and checked the data one another according to the include/exclude standards. Disagreement was resolved by discussions or with the third person. The Review Manage Software 5.0 was used for Meta-analysis. Results: Eventually, 2 randomized controled studies and 2 non-randomized controled studies met the inclusion criteria, with 163 subjects involved in the present meta-analysis. The meta-analysis demonstrated that Tai Chi exercise could improve the ankle flexor/extensor muscle strength and the knee extensor/flexor muscle strength, tested with an isokinetic dynamometer. The limb muscle strength increased significantly after Tai Chi exercise (P<0.01). Conclusion: The meta-analysis favours Tai Chi exercise for improving the lower-limb muscle strength in the older people. Methods: The assessable effects of Tai Chi (Chinese shadow boxing exercise) for improving the lower-limb muscle strength in elderly people. Methods: The PUBMED database (from 1950), EMBASE-ASP database (from 1974), Cochrane Library (from 1991), Elsevier sciences database (from 1990), OVID full text database (from 1997), Springer-link database (from 1997), The National Research Register database, ISI Web of knowledge (from 1963), Chinese Medical Citation Index / Chinese Chinese Knowledge Resource Integrated Database (CNKI, from 1915), VIP database (from 1989), and Wanfang database (from 1977) have been searched only for the English and Chinese literatures updated to Two researchers independently rated the methodological quality of studies, extracted and checked the data one another according to the include / exclude standards. Disagreement was resolved by discussions or with the third person. The Review Manage Software 5.0 was us Results for Eventually, 2 randomized controled studies and 2 non-randomized controled studies met the inclusion criteria, with 163 subjects involved in the present meta-analysis. The meta-analysis of that Tai Chi exercise could improve the ankle flexor / extensor muscle strength and the knee extensor / flexor muscle strength, tested with an isokinetic dynamometer. The limb muscle strength increased significantly after Tai Chi exercise (P <0.01). Conclusion: The meta-analysis favors Tai Chi exercise for improving the lower -limb muscle strength in the older people.