Abstract: In order to establish immortalized bone marrow mesenchymal stem cells line of Laoshan dairy goat,a previously constructed plasmid vector pcDNA3.1-EGFP-TERT was transferred into bone marrow mesenchymal stem cells(BMSCs)of Laoshan dairy goat.The stable transfected TERT-BMSCs was screened by the culture medium containing G418.The growth curve of the obtained TERT-BMSCs was determined by multiple subcultures.The stable TERT-BMSCs cell line was established by determining the genetic stability of higher generation.The results showed that BMSCs of Laoshan dairy goat transferred by TERT gene was stable.The growth curve of TERT-BMSCs was S type.After multiple passages,the normal rate of nuclear type of the P40 TERT-BMSCs was 88.24%.In conclusion,the transfected TERT-BMSCs cells had a good growth state,and their growth was stable and consistent with the characteristics of immortalized cells.Our study provides a theoretical basis for the application of the mesenchymal stem cells(MSCs)in tissue repair and the preparation of genetic engineering seed cells.