Mesenchymal stem cells(MSCs)are a kind of adult stem cells which have the capability to differentiate into multiple cell types as well as self-renew continuously.They have great therapeutic potential in tissue engineering,genetherapy,and stem cell transplantation.Bone marrow represents the major source of MSCs.In recent study,people found that there are also many MSCs in human umbilical cord.As a new source of MSCs,umbilical cord mesenchymal stern cells(UC-MSCs)has become the hot spot in MSCs research due to their advantages such as extensive resource,easy to be acquired,low viral contamination,higher frequency in the nucleated cells of umbilical cord and negligible antigenicity.This article reviewed biological characteristics,the advantages of UC-MSCs and their application in treatment of hematonosis.