The present invention provides a BM23 peptide obtained by mutating and modifying BMP-2. The BM23 peptide improves stability and duration ofefficacy relative to BMP-2, has an activity of promoting the differentiation of bone marrow mesenchymal stem cells into chondrocytes and promoting the proliferation of chondrocytes and can be used for repairing cartilage and/or treating osteoarthritis.