Abstract: The over-expression of Polo-like kinase 1(Plk1)is critical in the production and progression of multiple human tumors and is recognized as an effective target for the development of novel anti-cancer drugs. Currently a variety of small molecules targeting ATP or substrate binding sites have entered different stages of clinical trials. Polo-box domain(PBD)is a unique domain of Plks which plays an important role in the sub-cellular location of Plks and in the recognition of their substrates, therefore it has become an attractive target for the development of novel target-directed Plk1 inhibitors. In this paper, PBD function of Plk1 was introduced, the progress of small molecule and phosphoserine/phosphothreonine contained short peptide Plk1 inhibitors targeting PBD is summarized. Further development of this kind of inhibitors is also proposed.