Abstract: In order to estimate the application in the cellulose ethanol production by fermentation, an ethanol biosensor was used for cellulose ethanol in the broth during the ethanol fermentation process and the characteristics and patterns were investigated in this study. It was found that the results detected by the biosensor showed good linear relationship within the scope of 0.2-20.0 mg/100 mL, and the regression equation was y=5.00225x+0.72273 (R＝0.99976). The detector could detect the ethanol rapidly and accurately, and the response time was 20s, recovery ratio was of 99.3%-100.4%. The results showed no significant differences (P>0.05) between the detector and the traditional methods (i.e. gas chromatography and alcoholmeter). And the detector also showed some good merits such as high specificity, good repeatability, high precision (the detection lower limit of 0.2 mg/ml), high speed and stable. In this study, it could be concluded that the ethanol biosensor could be used for cellulosic ethanol determination, and it might replace the main methods (gas chromatography and alcoholmeter) for ethanol detection and would become the novel method for cellulosic ethanol estimation.