The study is devoted to the investigation of fea-tures of paint and varnish covering wear of the bot-tom and auger reaper of the harvest combines. The research objective was the definition of analytical expression of intensity of wear of paint and varnish covering of the bottom and the screw of harvest combine. In the analysis of the main existing tech-niques of determination the screw productivity it was established that the material movement of the auger was considered to be the movement of a uniform body with identical physical and mechani-cal properties on a uniform surface. It was revealed that the productivity of the screw of the harvest combine was significantly influenced by actual state of the surface of the bottom and the screw of the harvester on which cleaned grain-plant weight was transported. The nature of paint and varnish cover-ing wear of the bottom surface and the screw of a combine harvester was defined and it was revealed that the intensity of wear of paint and varnish cover-ing on these surfaces was uneven and increased from edges of the harvester to the middle and de-pended on the term of service. Analytical expres-sion for determination of wear intensity of paint and varnish covering of the bottom and the auger of harvest combines, including separate sites of the bottom and the screw of harvester was offered. Conducted researches demonstrated the necessity of technological processes development of coloring of surfaces of the bottom and the screw of the har-vest combines considering the specificity of work of the harvester and the intensity of wear of paint and varnish covering for the purpose of formation of covering steady to abrasion.