The effects of different pollen sources on pecan nut setting and development were studied by testing 9 pollinating varieties on 5 pecan clones. The results showed that the male variance contribution rate of all 5 clones were higher than 50%. Pollination with different varieties significantly affected the nut setting of individual females. The interaction between parents was observed. All nut characters except nut weight between male parents had a highly significant deviation. There was a large variation among the 7 nut characters across all 45 crossings. The largest coefficient variation reached to 26.33% that was observed for the nut weight of the 21^th clone, while the smallest one was 1.53% with the nut diameter of the 13^th clone. We selected suitable pollination cultivars for the 5 females based on the nut setting and other characters of each of 5 individual clones. For example, the 35^th clone and Janlin No.1 could be the pollen source for the 104^th clone; the 1^st clone, the 34^th, and Janlin No.1 could be male plants for the 28^th clone; the 5^th and 127^th clones for the 21^th; the 34^th and 6^th clones for the 13^th; the 35^th and 52^th and Jianlin No.1 clones for the 11^th as pollinating plants.