Evaluation of the performance of soil tillage machines is carried out in one or more indicators making a quantitative comparison between them or their criteria or generalized ones. These methods can provide an independent evaluation of one or another machine. They can not determine the degree of perfection of the machine. Proposed a comprehensive evaluation criterion the degree of perfection of the machines. It is used to estimate the plow, created by us and a standard one. It is proved that the new plow has a degree of perfection – a complex criterion D = 0,727. In this case D – criteria is 1.35 times higher than the standard plow, i.e. the new plow is more sophisticated than the standard, but not ideal.