In this research work, the study and determination of the performance indicators of the reliability of road-building machines is considered. As the results of this study, the performance indicators of the reliability of the motor grader XCMG GR 215 are presented. The performance indicators of the reliability of the motor grader are determined as: time between failures, the failure rate parameter and the average number of failures. The results of the study are presented as a function depending on the indicators of the flow parameter of refusal from the operating time of machines.