We demonstrated that combined treatment of Gilteritinib and Venetoclax has strong synergistic effects on inhibiting proliferation and enhancing apoptosis of FLT3/ITD cells, including Molm14, MV4;11, and TKI (Lestaurtinib)-resistant Molm14-R cells lines, as well as primary de novo or relapsed patient AML samples with FLT3/ITD mutations. Here, FLT3 is linked to acute myeloid leukemia.