The invention relates to the field of plant biotechnology, and discloses a bZIP1 gene of oryza granulata. Specifically, isolation cloning and functional identification of a bacterial-blight-resisting related gene from oryza granulata are carried out, and generally, a crop wild relative has the characters of disease resistance, stress resistance, high yield and the like. The oryza granulata is nearly immune to rice bacterial blight, and as the oryza granulata can not be hybridized with cultivated rice, a resistance gene in the oryza granulata is not effectively identified yet. The gene (OmbZIP1) in the oryza granulata is cloned and identified, and the gene is highly homologous with a bZIP type transcription factor in the cultivated rice. After an obtained transgenic material is identified, it is found that the gene can influence the resistance of rice to bacterial blight and enhance the disease resistance of the rice to part of bacterial blight microspecies.