Bioengineered T cells, which are the genetically manipulated T cells to express chimeric antigen receptor T Cell (CAR T) against leukemia-associated specific antigens, were applied to treat acute and chronic lymphocytic leukemia with CAR T. CAR T cells combined with cell-surface binding site and anti-CD19 chimeric antigen receptor can treat diseases through T cells transfection. CAR T cells can recognize the CD19 antigen on B cells with specific cell-surface loci. CAR T cells can proliferate by 1000 times and differentiate in vivo by the CD19 antigen stimulation, therefore, kill the acute and chronic lymphocytic leukemia cells effectively. This article briefly reviews the CAR T cells and the effect of CAR T cells on acute and chronic lymphoblastic leukemia.