The purpose of this study was to determine the optimal mixing ratio of olive oil, parmesan cheese, and nuts for preparation of pesto with spinach. Based on a surface response methodology (RSM), the independent variables were olive oil (100~300 g), parmesan cheese (25~75 g) and nuts (12~36 g). The dependent variables were physico-chemical properties as pH, color values (L, a, and b values), viscosity and sensory evaluation. pH decreased with increasing parmesan cheese levels. The L value decreased and the a and b values increased with increasing olive oil levels. Viscosity was negatively correlated with olive oil levels but positively correlated with the amounts of parmesan cheese and nuts. The addition of oil exerted a positive effect on gloss, and oily taste. In the sensory evaluation, the values of appearance, color, flavor, taste and overall acceptance were in the range of 4.4~7.2, 3.7~7.4, 4.4~7.1, 3.9~7.3 and 3.5~7.6, respectively. The sensory evaluation results showed significant values in appearance (p<0.01), flavor (p<0.01), taste (p<0.01) and overall acceptance (p<0.05). The optimal amounts of spinach pesto with olive oil, parmesan cheese, and nuts were determined by numerical optimization of a canonical model and graphical optimization. The optimal amounts were 175.29 g of olive oil, 49.51 g parmesan cheese, and 27.37 g of nuts per 100 g of spinach.