Osteoarthritis (OA) is a prevalent musculoskeletal disease that results in pain and low quality of life for patients, as well as enormous medical and socioeconomic burdens. The molecular mechanisms responsible for the initiation and progression of OA are still poorly understood. As such, mouse models of the disease are having increasingly important roles in OA research owing to the advancements of microsurgical techniques and the use of genetically modified mice, as well as the development of novel assessment tools. In this Review, we discuss available mouse models of OA and applicable assessment tools in studies of experimental OA.