Abstract:The gene of lightharvesting cholorophyll a/bbinding proteins was cloned by homologous sequences from Agropyron mongolicum Keng, named MwLhcb1. The fulllength of cDNA sequence was 1 138 bp,bioinformatics analysis showed that MwLhcb1 had an open reading frame of 801 bp, encoding 267 amino acids. The calculated molecular weight of MwLhcb1 was 28.21 kD and isoelectric point was 4.92. The MwLhcb1 protein had a conserved domain of Lhcb gene family in the secondary structure. Phylogenetic analysis revealed that MwLhcb1 amino acids sequences was highly similar with the homologous proteins of other species, it was more than 87%, and the similarity degree of protein with wheat was the highest, it is 99%. Realtime quantitative PCR analysis showed that MwLhcb1 gene was mainly expressed in stem and leaf, and the expression in the root was minimal. The expression of MwLhcb1 gene was affected by drought stress, and the expression of MwLhcb1 gene was different under the different levels of drought stress. The results could be a foundation for further study on the function of MwLhcb1 gene in photosynthesis and drought resistance of A. mongolicum. Meanwhile, it confirmed was wild relatives of wheat based on gene genetic and evolution, so we supported that was ideal donor for improving to wheat resistance.