The gradation impact on mineral granular masses segregation was studied for less segregation materials in pavement. The segregation test was built for pavement material detection

and mineral granular materials of different gradation index was designed by gradation theory. According to segregation test

the relation between gradation and segregation of granular masses was analyzed with gradation index

average diameter and diameter distribution index as the representation parameters of gradation. For granular masses with the same maximum diameter particle

the study shows that average diameter and diameter distribution index both having critical value

the critical value gradation has the minimize segregation and other gradations have more serious segregation. Critical value gradation is the gradation that remains reasonable voids when the next smaller particles fill the voids left by the bigger particles. It also found that average diameter and diameter distribution index have a good correspondence and the latter reduces with the former increasing. Finally

the results of mineral granular material segregation test and asphalt mixture segregation in pavement was analyzed.