Abstract: The study describes the design of a new conveyor system for multi-stage grain drying, providing superhigh-frequency (microwave) heating, subsequent lying and convective cooling in the fluidbed of the dried material. Based on the results of the experiment, a regression was established between the microwave radiation and the time of its single exposure to sunflower seeds from the condition of ensuring their subsequent germination. According to the experimental test data of the conveyor unit, a mathematical model of sunflower seeds drying process was developed which allowed to determine the total heating time to achieve the required final moisture content of the material, depending on the microwave power radiation and exposure time. The optimal parameters of sunflower seeds dryingare determined by solving the problem of minimizing specific running costs.