In this study, we report for the first time the use of C. Vulgaris microalgal strain containing cellulose in the modified form to be used as a catalyst support material for the production of hydrogen from the methanolysis reaction of sodium borohydride (NaBH4). Acetic acid, phosphoric acid, and hydrochloric acid (HCI) at different concentrations and impregnation times were used for the protonation of cellulose in the microalgal strain. The cobalt ions were added to this modified support material and, C.Vulgaris microalgal strain-supported Co-B catalyst was obtained. XRD, BET, FTIR, XPS, ICP-MS, TEM, and SEM-EDX analysis were carried out for characterization of the sample. The maximum hydrogen production rate from the methanolysis reaction of NaBH(4 )with this catalyst was 13215 ml min( )(-1)g(cat)(-1) In addition, the activation energy was determined as 25.22 kJ/mol. At the same time, reusability studies of the microalgal strain-supported Co-B catalyst were performed and it was found that there was no decrease in the % conversion for this catalyst, while the activity decreased. XRD, BET, FTIR, XPS, ICP-MS, TEM, and SEM-EDX. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.