Recently, more and more researches are focused on renewable energy from natural resources.  In the field of biofuel production, one of the popular topics is butanol production from solvent producing clostridia.  With more similarities with automobile fuel (e.g. octane number and energy content), butanol is considered a better biofuel candidate over other fermentable solvents.  Generally microbes produce butanol through acetone-butanol-ethanol (ABE) fermentation using agricultural commodities.  However, several limitations need to be resolved in order for butanol to be produced economically, including low yield, productivity, and titer of ABE fermentation.  Solvent fermentations were usually operated in batch reactors and resulted in low productivity with long fermentation time.  In this study, butanol was produced from a single-pass continuous fibrous bed bioreactor (FBB) by Clostridium beijerinckii ATCC 55025.  In single-path continuous fermentation, butanol can be constantly produced at high concentration with lower product inhibition by asporogenic Clostridium beijerincki.  Incorporation of FBB is able to help cell immobilization in a fibrous matrix at a high cell density and quick adaptation of higher concentration of toxic end products.  In this presentation, the process of butanol production was fine tuned to give better butanol productivity with optimized parameters such as medium composition and dilution rate.  Compared to the butanol productivity in batch reactors of 0.25 g/L·h, the butanol productivity in the single-path continuous FBB was increased to over 15 g/L·h with better fermentation conditions obtained from analyses.