Bio-hydrogenated diesel (BHD) is an interesting sustainable energy because of high heating value and environmentally friendly. This paper investigated parameters which affected to BHD production by catalytic deoxygenation reaction of fatty acid using nickel on silica catalyst. Three batches were firstly screened to find three parameters for optimization. The parameters consisted of type of solvent, oleic acid and palmitic acid, and the use of solvent. After that, Box-Behnken Design (BBD) in Design Expert program was used to optimize three operating conditions which were temperature, the amount of catalyst, and the amount of solvent using the selected reactant from screening experiment. The result of screening process showed that the conversions of fatty acid to fuel were almost 100 %. Therefore, the reaction temperature and the amount of catalyst were decreased to save the operating cost. Palmitic acid was selected as a reactant in optimization. In optimization, quadratic model was selected due to high r-square (0.9587) and p-value lower than 0.05. The model showed that the addition of solvent and high temperature reaction led to high selectivity of the desired product. The optimum operating condition was 53 mL of solvent, 1.4 g of catalyst, and 260 C reaction temperature with selectivity of 61.06 %. It was also found that solvent had the highest effect to the selectivity of the desired product compared to the amount of catalyst and reaction temperature.