The objective of this study is to evaluate the effect of the organic loading rate in anaerobic fixed-bed reactors using two support materials which were crumb rubber (recycled tires) and biopack ® with a hydraulic retention time (HRT) of 8h.The organic loading rate was modified with the sucrose concentration, with values of 6000 mg.L -1 , 12000 mg.L -1 and 18000 mg.L 1 .The results showed that the increased loading rate resulted in a reduction of both the production of hydrogen and the sucrose conversion for both supporting materials.The maximum value of hydrogen production and sucrose conversion was 50.9 % and 88% for the crumb rubber reactor, and 56.1 % and 74.4 % for the biopack reactor, for a loading rate of 11.26 g COD.L -1 .d -1 .In this loading rate, stability was observed in H 2 production.The ANOVA test showed statistically significant influence for both the loading rate effect and the supporting material type in the hydrogen production.