[Objective] The economic benefits of optimum fertilization of nitrogen

phosphorus

potassium and zinc of licorice in sierozem of the desert region area of Gansu Corridor were studied in order to provide technical support for the sustainable development of licorice industry.[Methods] A field experiment was carried out to study the economic benefits of optimum fertilization of nitrogen

phosphorus

potassium and zinc in sierozem of Sanbao Town

Minle County

Zhangye City

Gansu Province.[Results] With the increase of the fertilization of nitrogen

phosphorus

potassium and zinc

the fresh root yield of licorice was increased

but the increased amount of licorice under per 1 kg fertilization was decreased. The marginal yield and value of licorice were decreased

and the marginal profit showed a negative value eventually. In the desert region area of Gansu Corridor

the optimum application rate of nitrogen

phosphorus

potassium and zinc was 0.46

0.26

0.16 and 0.02 t/hm2

and the theoretical yield of fresh root at the optimum application rates were 12.81

13.35

13.06

12.76 t/hm2.[Conclusion] Sierozem has the low content of nitrogen

phosphorus

potassium and zinc

the application of nitrogen

phosphorus

potassium and zinc to licorice can increase the yield obviously

however

the fertilizer amount with the highest yield is not the optimum fertilization of economic benefits. The best fertilization amount is necessarily lower than that.