Articular cartilage, also called shock absorber, is a complex living soft tissue that covers gliding surfaces of joint and enables the joint to withstand weight bearing from human. Since there is no direct blood supply in the articular cartilage, it is generally hard to be repaired itself when it is injured. Although there have been several approaches to the repair of injured articular cartilage, current medical treatment is not able to give patients satisfactory treatment. Ultrasound has been used as one of physical therapy tools. Recently, there have been frequent reports that ultrasound has beneficial effect on the repair of bone fracture and soft tissue healing including articular cartilage. Although there have been appreciation of beneficial effect of ultrasound therapeutically, its mechanism is not fully understood and under investigation. From literature review, several researches tried to find optimal conditions of ultrasound such as intensity, frequency and duration on the repair of articular cartilage and it was reported that more effective ultrasound dose was found. However, different reports have different optimized ultrasound dose. It might be due to the variations of the type of ultrasound wave, intensity, frequency and duration as well as the different condition of experimental samples. Therefore, low intensity pulsed ultrasound (LIPUS) was investigated on the repair of articular cartilage and chondrocyte migration from this study. Also, optimal conditions of LIPUS dose on chondrocyte migration were investigated for the repair of articular cartilage.