Abstract: For research the effect of the economic traits of melon by nitrogen, phosphorus and potassium balanced fertilization, by means of quadratic component rotational design, the effect of N, P and K balanced fertilization on the yield of cucumber was studied in article. The mathematic model of balanced fertilizers was established. The optimal quantity of fertilizer, the effect of single factor and the interaction effect were studied. The results showed that between N and P, between N and K, between P and K had significant interacting effects, and the right fertilization ratio could improve the production of melon. The ratio of N:P:K were 2.03:1:3.36, and the amount of N, P₂O₅ and K₂O respectively were 157.5, 77.4, 260.38 kg/hm², and the highest yield of melon was 51893.205 kg/hm².