Objective: To observe the differences in the dynamic stability and kinematic and kinetic characteristics of the lower limbs between patients with knee osteoarthritis (KOA) and healthy individuals in the beginning stage of practicing Tai Chi Yunshou movement. Methods: Thirty Tai Chi beginners, including 15 patients with KOA and 15 healthy controls, were recruited to practice Tai Chi Yunshou movement for two hours under the guidance of a Tai Chi expert. A motion capture system and a three-dimensional force measuring table were used to collect and calculate dynamic stability parameters as well as kinematic and kinetic parameters of the left lower limb during the Yunshou movement. Results: Compared with healthy controls, patients with KOA demonstrated a smaller center of mass-center of pressure inclination angle (P=0.02), reduced mean and peak ankle dorsiflexion angle (P=0.01/P=0.02), reduced peak hip adduction angle (P=0.03), and increased peak knee flexion moment (P=0.04) during the Yunshou movement. Conclusion: Patients with KOA used adaptive postural strategies to maintain lateral stability in Tai Chi Yunshou exercise, but a comprehensive training programme should be recommended to reduce joint loading in lower limb flexion during the initial stages of exercise.