The extraction procedures for ${eta}$-glucans from cauliflower mushrooms (Sparassis crispa) were optimized by response surface methodology. Experimental design was used to investigate the effect of 3 extraction parameters (pH, extraction time, and ratio of water to raw material) on ${eta}$-glucan content. The parameter ranges investigated were 6-10 for extraction pH ($X_1$), 5-15 h for extraction time ($X_2$), and 10-30 for water to raw material ratio ($X_3$). The experimental results were in good agreement with a polynomial regression model by a multiple regression analysis ($R^2$=0.95, p=0.0074) for ${eta}$-glucan content extracted from cauliflower mushrooms. The optimal conditions for ${eta}$-glucan extraction from cauliflower mushrooms were determined as extraction pH of 6.05, extraction time of 8 h 55 min, and ratio of water to raw material of 19.74, showing 60.76% of the predicted content of ${eta}$-glucan.