Abstract: 【Objective】Aldehyde Dehydrogenase (ALDH) gene segment from Leymus Chinensis was cloned and the expression of it was researched under the different situations.【Method】ALDH gene segment was cloned by RT-PCR. The nucleotide and amino acid sequence of ALDH were analyzed. The expression of ALDH was researched by Real Time RT-PCR.【Result】ALDH gene segment was obtained which was 675bp and coding 225aa. The compare of nucleotide sequences indicated that it has 86% identity with rice ALDH1a (AB037421), and 85% identity with maize RF2C（AF348413）. By BLASTp Analysis, it shares 87%, 86% and 60% amino acid sequence identity with rice, maize and Arabidopsis thaliana ALDH, respectively, which containing conservation region of aldehyde dehydrogenase families. The data of Real Time RT-PCR indicated that the expression of ALDH was increased first, and then decreased under the inducing situations. As a whole, the responses of ALDH to salt and drought were much higher than to cold.【Conclusion】In this research, ALDH gene segment was obtained, and we researched the expression of ALDH. It established basis on cloning the span of ALDH in Leymus Chinensis.