The purpose of this study was to determine the optimal mixing conditions of three different amounts of spinach powder, butter and egg for the preparation of spinach muffins. The mixing condition for spinach muffins was optimized by response surface methodology. Egg was the most influential on height. The maximum point was achieved with 30.08 g of spinach powder, 247.69 g of butter and 184.97 g of egg. The optimum mixing rates of spinach power, butter and egg were 29.51 g, 252.24 g and 192.33 g for color, 32.43 g, 249.87 g and 180.90 g for overall quality and $28sim34;g,;250sim260;g;and;175sim210;g$ for maximum score of overall organoleptic quality, respectively.