Abstract:Acetic acid bacteria in solid fermentation substrate of Sichuan bran-vinegar were isolated and identified by using traditional cultured separation method，and the acid producing ability under the condition of pH，different fermentation temperature，oxygen supply were studied.The results showed that：a strain had strong acid producing ability was isolated，it was named Acetobacter pasteurianus through the method of molecular biology.Through the research on its metabolic conditions，the optimal fermentation conditions of this strain：optimal initial pH 5.0，the optimal temperature 35℃，shaker speed 150 r/min，the acid content up to 2.888 4 g/100 mL.