mRNA differential display technique was used to isolate genes(cDNA) induced by-0.7MPa PEG-6000 in leaves of grain sorghum seedling.A total of 53 differential expression cDNA fragments had been detected,including 5 absolute expression fragments induced by water stress,43 enhanced expression fragments,5 inhibited expression fragments.After further verified with reverse northern dot blot,thirteen fragments are proved to be positive.Aliging with GenBank databases found that 10 cDNA fragments showed high homologous while other 3 were poor supposed new genes.