Rationale. Theoretical and practical research in the field of abrasive wear of soil-cultivating implements, as a rule, is devoted to the processes of abrasion of the working surface of their parts. At the same time, the factor of changing the shape of an abrasive particle as it moves along the wear plane remains outside the scope of research. Failure to take into account the above-mentioned factor leads to incorrect conclusions and has a negative impact on the development of technology for manufacturing, strengthening and restoring structural elements of agricultural equipment. The purpose of the work is to conduct theoretical studies of the process of wear of the abrasive fraction of the soil when it moves along the working surface of parts of soil-cultivating implements. Materials and methods. The discovery of the goal was carried out using well-known theoretical research in the field of abrasive wear; integral calculus and the basics of tribology were used. Results. The result of the study was the derivation of a formula reflecting the degree of change in the geometry of an abrasive particle, taking into account the magnitude of its movement along the friction surface and the pressure of the soil mass. In this case, the determining parameter of its wear rate is the magnitude of the external force. Theoretical studies were considered in relation to cultivator tines. It is shown that the obtained mathematical expressions can be used for virtually all parts of tillage implements. Conclusion. The resulting mathematical equations indicate the possibility of the presence of three factors in the wear process: scratching; contact deformation; rolling depending on the change in the shape of the abrasive substance as it moves along the friction surface.