[Objective] To solve problems of drought, waterlogging, salination and infertility in salt soil and provide theoretical basis for the improvement of the saline soil in Hexi Corridor.[Method] Based on the principle of acid and alkali neutralization, ion exchange and the soil structure improvement method, we mixed in proportion of self-developed saline control agent, organic fertilizer and special fertilizer for liquorice, and carried out the field test experiments, evaluated the effect of mixed fertilizer on saline soil improvement.[Results] The fertilizer formula with the best functional improvement to saline soil was in the weight ratio:0.072 4:0.905 1:0.022 5 for salinity control agent, organic fertilizer, and special fertilizer for liquorice, respectively. The application amount of the functional improvement fertilizer was significantly and positively related to the total porosity of the meadow solonchak, the aggregate, water holding capacities, cation exchange capacity(CEC), organic matters, available NPK, licorice agronomic characters and the fresh weight of root and were negatively related to the bulk density, pH value and the salt content. The best application amount was 24.95 t/hm², the theoretical yield of the licorice fresh root(y) was 13.45 t/hm². The effect of different saline soil conditioners on bulk density, pH value, total salt and fungal changed as control > Wofenglong saline soil improver > salt abundant saline soil improvement fertilizer > functional improvement fertilizer. The effects on the total porosity, the aggregate, bacteria, actinomyces and enzyme activity changes as follows:functional improvement fertilizer > salt abundant saline soil improver > Wofenglong saline soil improver > control. Compared with the control, the functional improvement fertilizer reduced bulk density, pH value, total salt and fungi respectively by 13.38%, 7.91%, 39.82% and 55.56%, and increased the total porosity, the aggregate and liquorice root fresh weight respectively by 15.42%, 56.36% and 21.62%. Bacteria, actinomyces, sucrase, urease, phosphatase and polyphenol oxidase increased by 60.26%, 84.62%, 65.23%, 79.52%, 68.42% and 69.35%, respectively.[Conclusion] The application of functional improvement fertilizer in the meadow solonchak could effectively improve the physical, chemical and biological properties, and increase the soil enzyme activity and the water holding capacity of the meadow solonchak on the Hexi Corridor in Gansu Province.