Evaluation of harvest and postharvest treatment quality of the grains is affected by usage of appropriate equipment and technology. The grain damage depends on its physical and mechanical features. The corn planting has significant representation in European conditions, mainly for food industry purposes. In the work, we were focused on observing of the drying temperature’s impact on the micro-damage of the seeds. The solution of the issue described in the work is closely related to the preparation and solution of the education project KEGA 039SPU-4/2017, and a scientific research project VEGA 1/0718/17 „Study about the effect of technological parameters of the surface coating in agricultural and forestry techniques for qualitative parameters, safety and environmental acceptability“.