The characteristic of stress and load transmission in the semilunar cartilage model was studied with three-dimensional photoelastic method based on the principle of biomechanics. In addition to the liner function, the menisci may also provide with significant load-bearing capacity, The bearing capacity of external semilunar cartilage is larger than that of the internal one. Besides, the capsule and other soft tissue of the knee joint also participate in the load transmission. This study suggests that application of three-dimensional photoelastic method for the semilunar cartilage research may be a useful mean and with widespread prospect.