To build up a fertilization index system for winter wheat in Guanzhong irrigation area of Shaanxi, the data of 95 “3414” field experiments on winter wheat carried out in 2008 were analyzed; relative yields of the fields, i.e. 70%, 80%, 90% and 95%, were set as indices for grading abundance of soil nutrients; relationship between fertilization rate and yield of each field experiment site was simulated with a linear quadratic model; and an optimal economical fertilization rate was determined for each experiment site. In the end, a model for recommendation of N, P₂O₅ and K₂O application rates for winter wheat in this area was established based on the measurements of alkalytic N (AN), available P (AP) and available K (AK) in the soils and fertilization rates were recommended for fields different in soil fertility level. In wheat fields with the content of AN being very low (＜50 mg kg^-1), low (50~80 mg kg^-1), medium (80~120 mg kg^-1) or high (＞120 mg kg^-1), the application rate of N 190~230, 150~190, 110~150 and 0~110 kg hm^-2 was recommended, respectively; in fields with the content of AP being ＜10, 10~20, 20~35 and ＞35 mg kg^-1, the application rate of P₂O₅ 130~160, 110~130, 90~110 and 0~90 kg hm^-2 was, respectively; and in fields with the content of AK being ＜90, 90~150, 150~190 and ＞190 mg kg^-1, the application rate of K₂O 120~150, 90~120, 70~90 and 0~70 kg hm^-2 was, respectively. Demonstration trials showed that compared with farmer’s practice, recommended fertilization increased the yield and profit of winter wheat on average by 789 kg hm^-2 and 1 227 yuan hm^-2, and fertilizer contribution rate and agronomic efficiency by 8.2% and 1.7 kg kg ^-1, respectively.