Abstract: A mathematical model was established to find the optimum fertilization scheme of peanut new variety (‘Qinghua No.7’) with the design of ordinary second order rotational regression of three factors, in which N (nitrogen), P (phosphorus) and K (potassium) were independent variables and peanut yield were dependent variables. It discussed the single factor effect, interaction effect and best fertilization of N, P and K fertilizer through the inspection of the regression equation and effect analysis. The results showed that N, P and K fertilizer had significant influence on yield increasing of peanut, and the rank of factor effects on peanut yield was K(X3) >P(X2) >N(X1). The interactions of N and P for peanut yield were extremely significant. The optimum application rates for‘Qinghua No.7’achieving high yield were the best combination of fertilizer application: N fertilizer 106.08-133.92 kg/hm², P fertilizer 159.12-200.88 kg/hm², K fertilizer 138.28- 161.72 kg/hm².