The combination of Tofu manufacturing waste and digester sludge was studied for fermentative H₂ production in batch and continuous modes using a mixed culture. In order to increase the solubilization of organic substrates from Tofu waste, various pretreatments including heat-treatment, acid/alkali addition, and sonication were applied alone or in combination with others, and high concentrations of soluble carbohydrate (~ 10 g/L) were obtained with 0.5%(w/v) HCl at 110oC. Digester sludge was added to the Tofu waste as a supplementary nitrogen-source, and incubated with a mixed H₂-producing culture. Optimal mixing ratio of digester sludge was 20% (v/v) under batch conditions at 60oC and pH 5.5. In continuous experiments using a CSTR, the reactor was initially fed with synthetic media containing 1% (w/v) glucose at a HRT of 12 hrs and the ratio of the pretreated Tofu waste and digester sludge was gradually increased from 20% to 100% (v/v). After the stabilization of the reactor for H₂ production, the effects of HRT and pH were investigated. With decreasing HRT, volumetric H₂ production rate increased. The H₂production performance was not affected by pH 5.5 - 6.0, but, at pH 5.0, the reactor became unstable. The composition of headspace gas in the reactor was constantly kept at 50-60%(v/v) of H₂ gas and no appreciable CH₄ was detected during the fermentation. The maximal volumetric H₂ production rate was 7.8 L H2/L/day. This study indicates that the combination Tofu waste and digester sludge could be considered as suitable substrates for H₂ fermentation.