Objectives: Thai yoga is a traditional Thai exercise used for improving health-related physical fitness. Many studies have evaluated these effects, but their results remain inconclusive. This meta-analysis aimed to examine the effectiveness of Thai yoga on physical fitness. Design/Methods: PubMed, EMBASE, CINAHL, Cochrane library, Thai Library Integrated System (ThaiLis), Physiotherapy Evidence Database (PEDro), National Rehabilitation Information Center (Rehabdata), Scopus, Web of Science, Thai University library databases/journals, and Thai Physical Therapy database up to March 2016 were searched for randomized controlled trials (RCTs) examining the effect of Thai yoga exercise compared with normal daily activities as controls, in any language. The weighted mean difference (WMD) and 95% confidence intervals (95% CI) were performed using the random-effects model. Results: Seven RCTs met the inclusion criteria. Thai yoga training significantly improved body flexibility by 3.9 cmafter 4weeks [95%CI =3.9–4.0; p< 0.001: no heterogeneity w2 = 0.66, d.f.2, p= 0.7; I2 0.00%]and8.9cmafter 8 weeks [95% CI = 7.4–10.5; p< 0.001: no heterogeneity w2 = 0.16, d.f.2, p= 0.9; I2 0.00%] compared to controls. It also significantly increased range ofmotion (ROM)of right shoulder extension by 1.5 degrees at week 8, compared to controls [95% CI= 0.12–2.81; p=0.03; low heterogeneity w2 = 1.61, d.f.1, p= 0.2; I2 37.9%]. Greater ROM for right shoulder abduction was observed after 12 weeks compared to controls [22.2 degrees (95%CI=20–24; p< 0.001): no heterogeneity w2 = 0.29, d.f.1, p= 0.6; I2 0.00%]. Conclusions: Thai yoga exercises appeared useful, in particular, on body and right shoulder joint flexibility. Regular stretching exercise of Thai yoga and/or in combination with exercises could promote health-related physical fitness.