To enhance the butanol productivity and reduce the material cost, acetone, butanol, and ethanol fermentation by Clostridium acetobutylicum SE25 was investigated using batch, repeated-batch and continuous cultures in a fibrous bed bioreactor, where cassava flour was used as the substrate. With periodical nutrient supplementation, stable butanol production was maintained for about 360 h in a 6-cycle repeatedbatch fermentation with an average butanol productivity of 0.28 g/L/h and butanol yield of 0.32 g/gstarch. In addition, the highest butanol productivity of 0.63 g/L/h and butanol yield of 0.36 g/g-starch were achieved when the dilution rate were investigated in continuous production of acetone, butanol, and ethanol using a fibrous bed bioreactor, which were 231.6% and 28.6% higher than those of the free-cell fermentation. On the other hand, this study also successfully comfirmed that the biofilm can provide an effective protection for the microbial cells which are growing in stressful environment. (C) 2016 Elsevier Ltd. All rights reserved.