One of the most expensive aspects of agricultural machinery operation is the provision of spare parts. In order to reduce the costs, a lot of agricultural manufacturers purchase spare parts produced by alternative manufacturers, products of which often do not correlate with the official manufacturer's product quality. There is also a significant part of counterfeit products on the market. Various sources estimate it from 9 to 30 % of total sales, depending on the type of spare parts. In order to reduce the supply of low-quality spare parts, organization of the spare part quality control system by the dealer side is suggested. The aim of the study is the rationalization of the techniques and quality control regimes of agricultural machinery spare part choice. Based on an experiment conducted among large number of spare part suppliers, the structure of controlled parameters of spare parts is identified. The relationship between the number of measurements, the probability of detecting defects and other probabilistic parameters for controlling the spare part quality is revealed. The authors suggest the methods of the measurement device choice from the wide variety of contact and non-contact tools used for spare part control. The functions for the determining of the quality control modes, while ensuring the greatest probability of detecting defects and the greatest productivity, are described. The comparison between the technological parameters of various measuring instruments was made.