Autogenous osteochondral graft is a clinically effective treatment for articular cartilage defect. It is reported that the mechanical properties of the grafted cartilage change after treatment. Articular cartilage is required various mechanical functions such as the load support. Therefore, it is important that the change of mechanical properties of a grafted cartilage is quantitatively investigated. The ultrasonic method was used to quantify the quantify the biomechanical change. In this report, we focused on the effect of the operation .The aggregate modulus, surface roughness and thickness of cartilage before and after the operation were compared. In results, mechanical properties were not affected by the operation were compared. In results, mechanical properties were not affected by the operation. The results suggest that the follow-up after the operation have to be given attention.