The article deals with the results of studies of the influence of mineral fertilizers on the yield of green mass of alfalfa in the conditions of the Ganja-Kazakh zone of Azerbaijan. Ganja-Kazakh region is one of the important, from the point of view of a sustainable developing agricultural sector, economic regions of Azerbaijan. Alfalfa is one of the most important cultures of Azerbaijan, it plays a major role in the development of animal husbandry. The use of mineral fertilizers is one of the necessary agrotechnical measures of agriculture, contributing to an increase in the yield of agricultural crops including alfalfa. Under the conditions of the Ganja-Kazakh zone, the restoration of the fertility of low-yielding gray-brown soil and an increase in the yield of green mass of alfalfa is important. In this regard, we were tasked to determine the effect of mineral fertilizers on yield and quality of green mass of alfalfa. The investigation has been carried out in 2016-2018 at the Fakhrali Experimental Production Practice Base of the Beekeeping Center in the Goranboy District of the Ministry of Agriculture of the Livestock Scientific Research Institute. The soil of the experimental plot is carbonate, gray-brown (chestnut), medium-heavy loamy. The content of nutrient elements decreases from top to bottom in meter horizons. According to the accepted gradation in the republic, these soils are poorly supplied with nutrient elements and need fertilization. The study used a variety of alfalfa AzNIHI-262, the area of plots 144 m2 (20x7.20 m), the repetition of the experiment 3-fold. Agrotechnical cultivation was carried out according to the accepted methodology for the conditions of the Ganja-Kazakh zone. The experience was laid according to the methodological instructions (M.V.AUA, 1975), the seeding rate was 15 kg/ha. As the mineral fertilizers are used: nitric-ammonium nitrate, phosphate-simple superphosphate, potash-potassium chloride. The full dose of phosphate and potash fertilizers was applied in the fall for plowing the first year of life of alfalfa, the second year of life was applied in early spring, and nitrogen fertilizers were used in the spring as top dressing after the first cut. On the basis of the conducted research, it can be concluded that in gray-brown (chestnut) irrigated soils in the Western zone of Azerbaijan in order to obtain a high-quality crop of green mass of alfalfa and the restoration of soil fertility in this zone should be applied mineral fertilizers in the norm. Ne0Pg0Ke0 kg/ha.