Abstract: Cyclin-dependent kinase (CDK), a core molecule regulating cell cycle, has its subtypes present in all stages of cell cycle. CDK family members are mainly divided into three categories according to their different functions: cell cycle regulators, transcriptional regulators, and functionally diverse or undefined regulators. Since the occurrence of different types of tumors is related to the imbalance of cell cycle regulation, the CDK family has become a hot target for the development of anti-tumor drugs. At present, the CDK targeted inhibitors are CDK4/6 inhibitors, and the drugs that act on other CDK targets are also under development, with more drugs being expected to be available in the near future. At present, some research and development institutions are dedicated to the development of CDK inhibitors acting on non-tumor diseases, but these are mostly still in the pre-clinical stage of research and development. This review summarizes the members of the CDK family that have been discovered and briefly introduces them, in the hope of providing some reference for subsequent CDK research.