Abstract: Covalent drugs are a type of inhibitors which exert their biological functions by irreversibly binding to the target through covalent bonds. With the marketing of kinase inhibitor covalent drugs against tumor, covalent drugs have regained the attention for drug discovery and have become a recent hotspot of anti-tumor drugs. In this paper, the action mechanisms, pharmacological advantages and the development strategies of modern covalent drugs are discussed and the recent research progress of anti-tumor covalent inhibitors is summarized, which provides a reference for the design of new anti-tumor covalent drugs.