Based on the highly homologous EST sequence of phosphoethanolamine N-methyltransferase(PEAMT) gene obtained from drought-induced cDNA library of Cleistogenes songorica,a full-length cDNA of PEAMT gene was isolated from C.songorica.Full length of CsPEAMT was 2 104 bp,containing a 1 506 bp ORF and encoding 501 amino acids.Comparative analyses revealed that the amino acid sequence encoded by CsPEAMT gene was highly homologous to PEAMTs from other plant species,and CsPEAMT had the highest similarity with that of Sorghum bicolor and Zea mays(93%).The expression patterns of CsPEAMT during drought stress were investigated by real-time quantitative RT-PCR analysis.The results showed that drought stress induced a large number of the gene expression in root and leaf.And the CsPEAMT expression level in leaf and root are 43.35 times and 13.25 times higher than that of control,respectively,then the expression level began to decrease afer rewatering.This study indicated that CsPEAMT may be a drought-related gene.