【Abstract】Protein proteolysistargeting chimeras (PROTACs) is a bifunctional chimera that can directly degrade target molecules. PROTACs linked ligands that bind to target molecules and E3 ubiquitin ligase via an intermediate linker, and then ubiquitinated to modify and degrade target molecules through proteasome. Due to the mechanism of action of PROTACs, they can be used to design and synthesize PROTACs that regulate proteins related to tumor development, to achieve the effect of tumor treatment. Currently, PROTAC molecules targeting multiple cancerrelated proteins (BET protein, TBK1, cdk4/6, AR and ER, etc.) have been shown to have good effects in vitro and in vivo experiments, and are expected to be a means for the development of clinical tumor targeted drugs. The development of PROTACs and its application in tumor therapy will be described in detail.