Abstract:In order to study the function of homologous SnRK2 transcription factor gene in Fraxinus mandshurica,the homologous of the SnRK2B gene was find in the transcriptome responsed to drought from Fraxinus mandshurica and a complete transcription factor gene was cloned by Homology-based cloning method, and it was named by FmSnRK2B. The SnRK2B promoter fragment was isolated and identified from the genomic DNA of Fraxinus mandshurica using the method of SiteFinding-PCR. The gene sequence and promoter sequence was analyzed by bioinformatics analysis and cis-acting element analysis respectively. The results show that the complete transcription factor gene contain a complete open reading frame of 1 074bp which encoded 357 amino acids. The cis-acting elements analysis indicate that the promoter contain abscisic acid response component ABRE and other stress-related components as HSE, MBS etc. Under drought stress, the expression level of FmSnRK2B changed with time extension, which was first rised and then dropped, that means the gene was related to stress tolerance in plants. This study has a great significance to reveal the mechanism of resistance of Fraxinus mandshurica.