Abstract: With a RIL population culture in peanut(Arachis hypogaea L.),the heritability analysis of(eleven) quantitative traits of root,for example,length of axial root,number of lateral root,thickness of root base(1 cm),thickness of root base(3 cm),root volume,fresh weight of axial root,dry weight of axial root,fresh weight of lateral root,dry weight of lateral root,number nodules of lateral root and number no-(dules) of axial root were analyzed.We evaluated number of genes controlling the characters and estimated relation analysis in the characters,and studied genes interaction of controlling the root characters based on their skewness and kourtosis values.The results revealed there was highly significant or significant differ-(ence) in 6 characters,in their parents.But regardless of marked difference or no in their parents,all of traits in RIL population showed continuous variation and large aggressive segregation.And coefficient of variation was small in the traits of length of axial root and thickness of root base(1 cm)(CV=11.27% and 11.22%,respectively).Peanut root characters were all quantitative traits genetically controlled by polygenes.For instance there were about 10 genes controlling number nodules of lateral root and fresh weight of lateral root and dry weight of lateral root.But there were about 5-7 gene in others characters,especially 5 genes in number of lateral root.Except for dry weight of lateral root(h_n=0.569) and number nodules of lateral root(h_n=0.545) and number of lateral root(h_n=0.542),the heritability of the others was lower in RIL populations.At the same time,gene interaction was observed in part of characters,transgressive segregation gene interaction observed in polygenes controlling length of axial root and thickness of root base(1 cm),significant complementary gene interaction detected in nodule number of lateral root and dry weight of lateral root and nodule number of lateral(root;)but not detected out or not significant in the others.There was significant correlation between dry weight of axial root,dry weight of lateral root and thickness of root base(1 cm),thickness of root base(3 cm) and root volume.Root(volume) was significantly correlated with thickness of root base(3 cm).There was no correspondence in relation to root(volume) between fresh weight of axial fresh and weight of lateral root.