Hemiarthroplasty is applied if one surface of natural cartilage has diseases but another cartilage surface is healthy. Ultra-high molecular weight polyethylene (UHMWPE), metallic and ceramic materials have been used for hemiarthroplasty. Degeneration of cartilage and wear of UHMWPE are problems that occurred in hemiarthroplasty. Mosaicplasty is applied when a part of cartilage has disease. Healthy cartilage specimen for mosaicplasty is taken from other healthy cartilage part. A new material for mosaicplasty is needed to reduce a burden on patients. In this study, artificial cartilage material was investigated as a material for hemiarthroplasty and mosaicplasty. Poly (vinyl alcohol) (PVA) hydrogel was investigated as a artificial cartilage material for hemiarthroplasty and mosaicplasty. PVA hydrogel was rubbed with cartilage tissue taken from porcine femur condyle in saline solution containing protein and hyaluronic acid in vitro. Coexistence of human γ-globulin (HGG) and hyaluronic acid (HA) had effect to reduce wear of natural cartilage and PVA hydrogel. PVA hydrogel was implanted in rabbit knee joint and a possibility of application for mosaicplasty was investigated. Fixation of PVA hydrogel by bone growth was succeeded. No abnormal inflammation and wear were observed after 4 weeks. Therefore a possibility of application of PVA hydrogel for hemiarthroplasty and mosaicplasty was shown.