BACKGROUND: Knee osteoarthritis (OA) is a major cause of disability as well as a burden on healthcare resources. Tai chi has been proposed as an alternative and complementary treatment for the management of knee osteoarthritis, but there appears to be no consensus on its usefulness. This study aims to develop an innovative tai chi rehabilitation program (ITCRP) for patients with knee OA, and to investigate the effect of ITCRP intervention on a range of outcomes including pain, function, balance, neuromuscular response, and biomechanics in knee OA. METHODS/DESIGN: We will conduct a prospective, single-blind, randomized controlled trial of 140 individuals with symptomatic knee OA. Patients will be randomly assigned into either an ITCRP group or a control group. The ITCRP group will participate in tai chi two or three times a week for 6 months. The control group will receive health education. After the 6-month intervention period, there will be a 6-month follow-up period with no active intervention in either group. The primary and secondary outcomes will be assessed at baseline, 6 months, and 12 months. Primary outcome measures will be a visual analog scale for pain, the Western Ontario and McMaster Universities Osteoarthritis Index,and the Lequesne Knee Score. The secondary outcome measures will include the Berg balance scale, knee and ankle proprioception, neuromuscular response, and 3D functional biomechanics. Furthermore, adverse events will be recorded and analyzed. If any participants withdraw from the trial, intention-to-treat analysiswill be performed. DISCUSSION: Important features of this trial include the randomization procedures, large sample size, and a standardized protocol for ITCRP for knee OA. This study aims to determine the feasibility of ITCRP for knee OA and provide data on the effects of ITCRP. Hence, our results will be useful for patients with knee OA as well as for medical staff and healthcare decision makers. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR-TRC-13003264.