In this study, therefore, hydrocarbon production from plant oil was studied through two-step reaction with hydrolysis and subsequent decarboxylation. During the hydrolysis step, hydrogenation was simultaneously conducted to produce stable saturated fatty acids, which may suppress undesirable side reactions during subsequent decarboxylation (19,20]. In the literature 15-21], furthermore, an organic solvent such as n was usually added to enhance the fluidity of the reactants and to avoid the deactivation of catalyst, even though only a few studies without any solvent can be found [19.22]. However, the use of such organic solvent requires additional separation and purification steps after the reaction, and it makes the whole process complicated. Therefore, the reactions of this study were conducted without any organic solvent so as to simplify the process for production of hydrocarbons as renewable diesel