[Objective] This study aimed to improve the taste and quality of buckwheat(Fagopyrum esculentum) seeds. [Method] Buckwheat seeds were fertilized by using a quadratic orthogonal rotation combination design to establish quaternary quadratic regression equations between N, P, K, organic fertilizers and soluble sugar, protein contents in buckwheat seeds. [Result] According to the regression equations, appropriately increasing the application amount of P fertilizer and maintaining the ratio of N fertilizer to organic fertilizer at 1:140 could improve soluble sugar and protein contents in buckwheat seeds. By simulation optimization using a computer,in order to ensure high soluble sugar and protein contents in buckwheat seeds, the optimal fertilization patterns of each fertilizer were: N, 535.35-581.10 kg/hm^2; P2O5,69.511 5-71.359 5 kg/hm^2; K2 O, 249.525-270.975 kg/hm^2; organic fertilizer, 76 590-80 514 kg/hm^2. The optimal fertilization ratio of N, P, K and organic fertilizers was8:1:4:1 114. [Conclusion] This study provided scientific basis for producing buckwheat products with good taste, high nutrition value and excellent quality.