Most plants are sensitive to NaCl.In order to identify the NaCl tolerance of Lotus corniculatus L.regenerants in vitro,the growth and rooting of these regenerants cultured in the MS medium supplemented with different concentration NaCl were determined in the experiment.The results showed that plants grew slowly and could not rooting,their leaves turned white when NaCl concentration was above 0.7%.When NaCl concentration was below 0.7%,the plants grew as same as the control.This method could be used in identifying salt tolerance of transgenic plants.