OBJECTIVE: To elongate the proliferation life-span of human umbilicus vein endothelial cell (HUVEC). METHODS: We synthesized the human telomerase reverse transcriptase mRNA (hTERT mRNA) by in vitro transcription, then transferred the hTERT mRNA into HUVEC in quicent stage by lipofect introduction. RESULTS: Telomerase expressed transiently in HUVEC, and the cell life-span was elongated for 7 population doublings. CONCLUSION: Telomerase can be reconstructed controllably and transiently in HUVEC by hTERT mRNA introduction, this method has the potential to be used to elongate the lifespan of cells cultured in vitro.