Tillage is the most energy-intensive soil operation. In the actual energy situation is important to explore and analyze the physical laws of soil cultivation processes, that demand large energy quantities, at the border of technical- and agricultural sciences. We studied the physical phenomenon’s occurring during the work with a rotary tiller and approximated the energy requirements with a computer simulation using Matlab Simulink environment. The model used was a simplified solid model of an FPP-1,3 type rotary tiller, used previously in real experiments to determine fuel consumption at various working parameters. The results obtained with the dynamic simulation were compared with the real measurements.