Objective:To isolate and identify exosomes derived from human umbilical cord mesenchymal stem cells (HUCMCS) and to testify the potential of hemolysis of exosomes. Methods:HUCMSC-derived exosomes were isolated and purified through ultracentrifugation. Western blot and transmission electron microscope were used to identify the characteristic of the exosome. Exosomes were incubated with human erythrocyte suspension to observe the hemolysis. Results:HUCMSCs derived exosomes expressed positive makers of CD9,CD81 and Alix,didn’t express the Golgi Body protein Gm130 as negative marker. The particles size displayed range from 40-120 nm. It can be seen a classical doughnut shape of exosomes through transmission electron microscope. And the exosome derived from HUCMSCs didn’t cause the hemolysis of human red cell. Conclusion:Exosomes secreted by human umbilical cord stem cells possessed classical characteristics of exosomes and had no effects on hemolysis,which provide the experimental basis of potential clinical use of HUCMSC exosomes for drug delivery.