Mitochondrion-orientated transportation of smart liposomes has been developed as a promising strategy to deliver anticancer drugs directly to tumor sites,and these have a tremendous potential for killing cancer cells,especially those with multidrug resistance (MDR).Herein we report a novel dual-functional liposome system possessing both extracellular pH response and mitochondrial targeting properties to enhance drug accumulation in mitochondria and trigger apoptosis of drugresistant cancer cells.