As more and more clinical trials about chimeric antigen receptor T cells (CAR-T) have been carried out successfully, the CAR-T are getting well-known. Thanks for genetic engineering, CAR-T has the tumor special antigen expressed on the surface. CAR-T therapy is the adoptive immunotheraphy for rapidly advancing tumors. This technology has made a great progress in both blood malignancies and solid tumor. However, CAR-T also meet many difficulties in the way of development. This review discusses the clinical application, challenges and developing trend of CAR-T.