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The carob-tree (Ceratonica siliqua L.) grows in arid to semi-arid Mediterranean areas and adapts well to poor soils. Carob pod, the fruit of carob tree is a sugar-rich biomass which may theoretically be ideal for biofuel production. During this study, the potential of hydrogen production from carob pod was evaluated in an anaerobic continuous stirred tank bioreactor using mixed microflora. A carob pod extract consisting of soluble carbohydrates at a concentration of 42.6 g/L was obtained from a standard extraction process. The reactor was operated at a hydraulic retention time (HRT) of 36 and 18 h and an organic loading rate of 155.8 and 311.6 mmol glucose/L/days respectively. The results showed a maximum hydrogen production yield of 8.4 L H-2 per kg of carob pod biomass or 0.43 mmol H-2 per mmol glucose consumed at the HRT of 18 h. Butyric acid was found to be the dominant metabolic product at both examined HRTs while propionic acid production decreased as HRT decreased. The present work suggests that carob tree, an alternative dryland forest crop, can be utilized for the efficient production of biohydrogen.