Abstract: The overexpression of doublecortin-like kinase 1 (DCLK1) is closely related to the occurrence and development of various malignant tumors. Discovery of novel anti-tumor agents targeting DCLK1 represents a hot spot in this field. So far, several DCLK1 small molecule inhibitors with excellent anti-tumor activity in vitro and in vivo have been designed and synthesized, which is expected to provide a new strategy for tumor therapy. This article reviews the research progress in the discovery, structure type, structural optimization, biological activity and mechanism of action of DCLK1 small molecule inhibitors, and provides research basis for the development of new anti-tumor small molecule inhibitors targeting DCLK1.