Tai Chi (TC) can be considered safe and effective intervention to improve pain and pain-related functional disability. However, it is unclear that whether aging individuals with Chronic Non-Specific Low Back Pain (CNS-LBP) can achieve positive results. This study, therefore, attempted to explore the effects of TC on pain and functional disability in CNS-LBP patients aged 50 years old or above. Forty-three individuals (aged 50 years old or above) with CNS-LBP were randomly assigned into three groups: Chen-Style TC group (n = 15), Core Stabilization training (CST) group (n = 15), and control group (n = 13). Participants in the TC group participated in Chen-style TC training program (three 60-min sessions per week for 12 weeks), individuals in CST group received 12-week Core Stabilization exercise on the Swiss ball, whereas individuals in the control group maintained their unaltered lifestyle. Pain intensity as primary outcome was measured using the Visual Analogue Scale (VAS), A BiodexSystem 3 isokinetic dynamometer was used to measure knee and ankle joint position sense (JPS) as secondary outcomes at baseline and after the 12-week intervention. TC and CST have significant effects in VAS for CNS-LBP patients (p< 0.01, TC group OR CST group versus control group in mean of the post-minus-pre assessment). However, the feature of joint position sense (JPS) of ankle inversion, ankle eversion and knee flexion did not occur, it showed no significant effects with TC and CST. TC was found to reduce pain, but not improve lower limb proprioception in patients with CNS-LBP. Future research with larger sample sizes will be needed to achieve more definitive findings on the effects of TC on both pain and lower limb proprioception in this population.