Abstract: The mitochondria-targeted TPP-PEI-LND was synthesized by mitochondria-targeted ligand triphenylphosphine(TPP)and therapeutic drug lonidamine(LND)conjugated to low molecular weight branched polyethyleneimine(PEI). TPP-PEI-LND was verified using ¹H NMR; in vitro release was determined by the dialysis. Besides, the cytotoxicity and mitochondria-targeted potential of TPP-PEI-LND were investigated in HeLa cells. The results showed that TPP-PEI-LND was successfully synthesized and it exhibited the feature of extended-release. Hence, TPP-PEI-LND could deliver LND to mitochondria, resulting in significantly enhanced efficacy of LND.