When modeling and performing calculations on heat and moisture-exchange in a grain layer, it is considered that the drying coefficient remains constant. However, our observations allowed to put forward the hypothesis that the value of the drying coefficient varies depending on the parameters of the drying agent. With the use of variety of electrical effects for intensification of grain drying, the data was obtained which reveals the change in the rate of drying. This allows suggesting that drying coefficient depends not only on the parameters of utilized air but also on parameters of electrophysical effects. A number of experiments were conducted to get the regression equations reflecting how drying coefficient depends on these factors. Experimental data was processes with the use of application software. Obtained regression equations turned out to adequately describe the relation between drying coefficient and parameters of the drying agent and electrophysical effects. These dependencies can be used to simulate the process of drying more accurately and to look for the optimal modes of drying.