Abstract: Phosphoinositide 3-kinase(PI3K), a key regulator in the PI3K/AKT/mTOR signaling pathway, plays a critical role in regulation of cell growth, differentiation, metastasis apoptosis, and angiogenesis processes. Abnormal activation of PI3K is closely related to the development of many types of human cancers. PI3Kδ is an important isoform of PI3K family, mainly expressed in leukocytes, which makes it an attractive target for the treatment of hematological malignancies. Great efforts in both industry and academia have been made to develop PI3Kδ selective inhibitors as anti-cancer agents. This review attempts to provide an overview of recent advances in the research of PI3Kδ selective inhibitors, fueling the progress of the ideal selective PI3Kδ inhibitors in the future.