Main tillage is a common part of the crop production technology that causes substantial changes of the surface structure of soils and affects its various physical, chemical and biological properties. It can be done with a diverse set of methods and techniques understood as an action of tillage implements on a soil by dint of active parts having various modifications that alter tillage composition of soil significantly. The role of mechanical soil treatment in the modern agriculture has been changing dramatically. Widespread introduction of alternative techniques (such as plowless, minimal and soil-protective tillage) in the production necessitated the clarification of significance of the moldboard plowing in alteration of structural and aggregate properties of soil in various physical geographical zones. Based on our experimental data the plowless soil tillage retains more nutrients than that of the disk harrowing. In particular, nitrogen content of the soil is 42.6 % higher, while with chisel plowing the difference is 41.2 %. It can be derived from analyzing these data that preservation of soil fertility and its structure requires that more attention is paid to the plowless tillage, and in case of weed infestation it should be supplemented with the chisel tillage to a depth of 0.45 … 0.5 m which improves structure and water-air climate of the soil, and on average increases yields by 18-24 %.