Fifty-two China-bred and introduced cottons with Fusarium and Verticillium wilts resistance were used to study their pedigrees and the effects of pedigree proportion on yield components. The results indicated that Deltapine and Stoneville descents contributed to the most of the varieties in proportion, followed by Foster. According to the proportion of main germplasm resources in different cottons,52 varieties were classified into four groups. Different genealogy composition had different effects on yield components, especially on boll weight and seed index. The varieties of first group with higher proportion of Deltapine had higher boll weight than those of second group with lower proportion of Deltapine and higher proportion of Stoneville. The seed index of the first group was higher than that of the second and the fourth group with higher proportion of Foster.