The research objective was the increase of efficien-cy of mechanized processes in plant growing coordina-tion of parameters of grain-harvesting and drying com-plexes. The research problems were 1) to carry out the analysis of functioning of the mechanized process of cleaning and drying of grain crops, to prove ways of increase of their efficiency on the basis of coherence of operational and technological parameters; 2) to estab-lish interrelation of productivity of grain-harvesting and grain drying complexes; 3) to confirm theoretical re-searches under production conditions. By the research-es it was established that rational productivity of drying complex was influenced by hardware of grain-harvesting process, the reliability of grain-harvesting equipment, the cost of made production per hectare and other pro-duction factors. Violation of agrotechnical terms as a result of influence of climatic conditions on the produc-tion of grain crops harvesting leads to considerable losses of production and decrease in the profit of pro-duction. For the increase of efficiency of functioning of technological line on the basis of economic and mathe-matical modeling productivity of grain drying equipment depending on the number of combines, their level of operation, technical reliability and the influence of weather conditions is proved. In the study the coeffi-cients of weather conditions for three scenarios are re-vealed: favorable, average and adverse. Calculations showed that at the increase in seasonal load of the combine and efficiency of time of change of drying equipment its rational productivity needs to be reduced, and with increase in efficiency of time of change of the combine, the cost of made production productivity should be increased. The growth of the price of made production by 30 % imposes requirement to the in-crease of rational productivity of grain drying equipment to 20 %. Production tests confirmed theoretical calcula-tions and allowed to gain economic effect of 1500-1700 rub/hectare.