The aim of this research was to detect the efficiency of the dyes on evaluation of mechanical damage in corn seeds and the influence of these damages on physiological quality. Corn seeds of cultivar AG 122 from differents lots, manual and mechanically harvested were used damage detection was made by differents analysts using the dye Amaranth 0,1% for two minutes and Idione 4% for five minutes. The seeds of each lot were separeted in four categories scaled from zero to tree according presence, localization and intensity of damage. The Amaranth dye provided smaller variation than Iodine in the mechanical damage evaluation by differents analysts. After the separation in categories, the seeds were evaluated in their physiological quality by germination test and vigor tests. The seeds scaled zero showed the best physiological quality, followed by 1, 2 and 3. It sugest that the classification of damage in categories permits separation of lots with different quality.