Osteoarthritis is one of the most common forms of arthritis. It is also the most common disease in older adults. In North America, 70% of people with osteoarthritis are older than 65 years old. And 30% of women over the age of 65 have varying degrees of osteoarthritis. In the United States, it is the leading chronic disorder that causes patients to waste away. The incidence is high, with 8 million people affected in the United Kingdom and 27 million in the United States, and the number is increasing. People with a history of joint trauma, obesity, and long periods of seated work are more likely to develop osteoarthritis. It usually affects weight-bearing joints, such as the lumbar spine, hip and knee joints. Primary osteoarthritis of the hip is less common in China, while primary osteoarthritis of the knee is the most common, so osteoarthritis generally refers to osteoarthritis of the knee. Osteoarthritis not only causes joint pain, but can also cause joint deformation (inversion or valgus deformity), flexion contracture, limited flexion and extension, walking strangulation, instability, falls, and even inability to walk. The pain affects walking, which in turn increases obesity, increases the burden on the heart and lungs, and decreases general health. It also causes patients to become psychologically depressed due to concerns about increasing obesity. Osteoarthritis cannot be cured, but its further development can be prevented or slowed. Weight loss is a very effective prevention method, especially for obese patients. There is clear evidence that a patient’s weight is positively correlated with the severity of osteoarthritis. Weight loss not only reduces the stress on the tibiofemoral joint of the knee, but also reduces the stress on the patellofemoral joint to prevent the onset of disease, reduce symptoms, and slow the progression of the disease. From the perspective of osteoarthritis prevention, swimming is the best exercise to achieve the required amount of exercise, but also to avoid overloading the knee joint and increasing the wear and tear on the joint cartilage. Climbing, excessive up and down stairs, soccer, tai chi and other exercises that overload the knee joint in a flexed state are not appropriate exercises. Exercises that increase muscle strength are also very beneficial. For example, increasing the strength of the quadriceps muscle can increase the stability of the knee joint, reduce the abnormal force on the knee joint, and avoid or slow down the development of osteoarthritis. However, such exercises should not overtax the muscles. Exercises that increase joint mobility are also essential to prevent osteoarthritis and can be a way to reduce stiffness, increase joint mobility, and prevent soft tissue contractures. Other things that can play an important role in preventing the onset and progression of osteoarthritis include education for people with osteoarthritis, etc.