In this study, bio-hydrogen generation potential of sugar-beet processing wastes (sugar-beet processing wastewater and beet-pulp) through dark fermentation was investigated. For this purpose, four different experimental set-ups were used. In the first set-up, sugar-beet processing wastewater was used along with four different cultures to investigate the effect of culture type on bio-hydrogen production. In addition, unseeded reactor was prepared to investigate bio-hydrogen production potential of indigenous microorganisms. The highest bio-hydrogen production yield (87.7 mL H2/g COD) was observed in the unseeded reactor. In the second set-up, beet-pulp was compared with sugar-beet processing wastewater in terms of bio-hydrogen generation potentials at an initial COD level of 4.5 g/L. In the third set-up, bio-hydrogen productivities of only beet-pulp and co-digestion of beet-pulp and sugar-beet processing wastewater at high COD values were investigated. The results of third set-up revealed that the reactor fed by 20 g/L COD beet-pulp provided the highest bio-hydrogen production yield (95.6 mL H2 /g COD). Finally, in the fourth set-up, the effects of five different pretreatment methods on solubilization of beet-pulp were investigated. Then, three out of five pretreatment methods were chosen to compare the corresponding bio-hydrogen productivities. Maximum bio-hydrogen production yield (115.6 mL H2/g COD) was observed in reactor which contained alkaline pretreated beet-pulp. Based on the results obtained in this study, it is postulated that, bio-hydrogen production from sugar-beet processing wastes by dark fermentation can not only enable waste minimization but also contribute to sustainability via valuable bio-based product formation from wastes, namely bio-hydrogen.