Grain hardness of wheat is a major index of its technological usefulness. The present study was undertaken to evaluate changes in the grain hardness in relation to a ripe stage and a harvest date of wheat. The grain of winter (cv. Roma) and spring (cv.Igna) wheat was isolated by hand from cars, which were earlier taken from experimental plots and dried. Measurements of single kernel hardness were made using a SKCS 4100 set. For cv. Roma, in the grain filling period until to the milk ripe stage, values of hardness index (HI) were decreasing from 78 to 45 [-]. However, in the ripening period, there was observed successive increase in HI value. Then, in first two weeks from when wheat reached the full ripeness, the considerable decrease in the HI from HI z 63 to 33 [-]took a place. For cv. Igna, in the grain filling period until to the milk ripe stage, there did not take a place the decrease as for cv. Roma, but the gradual increase in grain hardness. Then, in whole ripening period as well as during wheat harvest until 2nd week after maturity, the HI decreased successively from 98 to 70 [-]. Further delay in doing harvest, from 2 weeks to I month after maturity, exerted much weaker influence on the HI decrease for both cultivars.