Abstract: Abscisic acid-insensitive 5(ABI5) protein was a basic leucine zipper(bZIP) transcription factor containing a basic DNA-binding domain linked to a leucine zipper domain and ABI5 protein response abscisic acid. We studied the FmABI5 expression pattern in signal induction and regulation, and analyzed gene function in metabolic regulation of Fraxinus mandshurica. The ABI5 gene was cloned from F.mandshurica, named FmABI5. The molecular structure of FmABI5 was analyzed by bioinformatics software. Abiotic stress by polyethylene glycol(PEG), salt(NaCl) and low temperature(4℃), and signal induced by abscisic acid(ABA) and gibberellin(GA) were used in the study. The expression patterns of FmABI5 induced by abiotic and signal induction were analyzed. By bioinformatics analysis, FmABI5 is 1 455 bp, and contains the complete ORF, encoding 484 amino acids. FmABI5 is a hydrophobic protein without signal peptide but with one transmembrane ability. The alpha helix, extension chain and random coil are distributed throughout the protein. By molecular evolution analysis, the genetic distance of FmABI5 gene between F.mandshurica and Sesamum is relative close. The gene heredity distance is farther with Solanum tuberosum, S.pennellii, S.torvum and Capsicum annuum, explaining the far genetic relationship with them. After abiotic stress, FmABI5 gene expression levels varied with abiotic stress time with fluctuations, but after 6, 48 and 72 h treatment, FmABI5 gene for three abiotic stress treatments were up-regulated, indicating FmABI5 genes are responsive to abiotic stresses. Therefore, the signal induced by exogenous ABA and GA regulate transcription expression of FmABI5 together.