Correct application of mineral fertilizers provides an increase in productivity, improving the quality of products. The conditions for plant nutrition in soil depend on the doses, timing and methods of fertilization. For the effectiveness of mineral fertilizers, in case of its long-term use, a detailed, systematic study of soils and their impact on yields and on the plant resistance is necessary. The search for environmentally friendly ways, increasing crop yields and improving the quality of products, is an important scientific and practical task of modern agriculture. The purpose of this work is to study the effect of long-term use of mineral fertilizers on the productivity of six-field crop rotations with different grain crops saturation. During the long-term experiments, the effect of mineral fertilizers on the fertility of sod-podzolic medium-loamy soil and on the productivity of crops of six-field crop rotation was studied. As a result of the research it was established that the use of mineral fertilizers in the field crop rotations at a dose of N60P60K60 in relation to the variants without fertilizers contributed to an increase in yield by 24.6–37.8 %, fodder units by 17.7–35.8 %, collection of dry matter by 15,.4–33.8 %, exchange energy by 16.5–35.2 %, regardless of the degree of saturation of grain agrophytocenosis. The application of mineral fertilizers in field crop rotation contributed to a significant increase in the yield of field crops, which confirms the high responsiveness of crop rotation to mineral fertilizers. It should be noted that the crop rotation with the least grain saturation is more responsive to the use of mineral fertilizers: an increase in the yield per hectare of crop rotation area was 11.2–16.0 % compared to the variant without fertilizers. Long-term use of mineral fertilizers for all crop rotations increased the yield of feed units by 20 % in comparison with the natural fertility of the soil.