Improving the reliability and durability of internal combustion engines makes it possible to increase productivity and reduce the cost of operation. The study of nature and magnitude of piston rings wear is relevant and represents a scientific novelty. During the operation of internal combustion engines, it is almost impossible to determine the influence of various factors on the wear rate and the resource of piston rings. One of the most accurate ways to study the wear intensity and the service life values of internal combustion engines piston rings during operation is the statistical method. The method of mathematical statistics allows us to study the nature and magnitude of individual parts wear with a sufficient degree of accuracy, to determine the main causes of wear, to outline ways of increasing the parts wear resistance, to establish durability criteria, to reasonably assign standard service life of parts and plan the parts need for any period with a given probability, with climatic conditions being taking into account. The article presents the collected statistical material on the internal combustion engines piston rings wear of construction and road vehicles operated at construction sites of Rostov region. It has been processed according to the normal Gauss law and data on the wear and service life of piston rings are obtained. The obtained experimental data on the wear of piston rings in height are reliable to the distribution law and can be used to determine the intensity of engines piston rings wear at repair enterprises.