A series of Vitamin E (vitE)-labeled PEIs (PEI-vitE(n)) were synthesized and showed excellent complexation ability with plasmid DNA (pDNA). The cellular uptake of PEI-vitE(n)/pDNA-complexes was greatly enhanced with the increase of vitE labeling, which is much better than that of control PEI25 in three different cell lines. PEI-vitE(6) showed the best performance in gfp pDNA delivery and following GFP expression in HEK-293A cells. In addition, in vivo gene delivery in living mice also confirmed that PEI-vitE(6) showed low toxicity and efficiently delivered gfp pDNA to the cells of liver and lung tissues for gene expression.