Objective To explore the experimental conditions of labeling rabbit bone marrow mesenchymal stem cells (Rb-MSCs) with 5,6-carboxyfluorescein diacetic succinimidyl ester (CFSE) and to investigate the impact on the biological characteristics of Rb-MSCs in vitro.Methods Rb-MSCs were separated and purified by whole bone marrow adherent culture and then were identified by morphology and surface markers.Rb-MSCs were labeled with CFSE and the labeling effect was measured by flow cytometer.The proliferation capacity of labeled cells was detected with CCK-8.The differentiation capacity of labeled cells was investigated by being induced to osteoblasts and lipoblasts.The capacity of labeled cells to secret vascular endothelial growth factor (VEGF) was detected by VEGF ELISA kits.Results The primary Rb-MSCs adhered in 48 h,being fusiform and colony-like growth.Subculture cells became fibroblast-like cells in order with uniform configuration.Most (above 98％) cultured cells expressed the surface markers CD29 and CD44 except for CD45.Compared with other labeling conditions,10μmol/L final concentration of CFSE and 10 min was the best one with a 100％ labeling rate and high fluorescence intensity.Compared with unlabeled cells,the ability of the labeled cells to proliferate and to secrete VEGF was not significantly decreased (P ＞ 0.05).Moreover,the labeled cells had osteogenic and adipogenic differentiation capacity.Conclusions It was a simple and efficient method to label Rb-MSCs with CFSE,especially in a short-term.The capacity of cell proliferation,differentiation,and secretion were not affected.