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Objective To analyze and select the genetic variation of growth traits among provenances and families of Juglans mandshurica, in order to promote the selection and breeding of J. mandshurica superior varieties. Method In this study, the growth characteristics (tree height, annual growth of tree height, ground diameter, crown width, straightness, branch angle, number of side branches and taperingness) of 28 J. mandshurica families (6-years-old) within 4 provenances at Wanrenhuan Forest Farm were measured and analyzed. Result The results of analysis of variance showed that most of the traits reached extremely significant differences among various sources (P < 0.01). The phenotypic and genetic coefficient of variation of these traits ranged from 12.865% to 43.171% and from 5.176% to 25.533%, respectively. The family heritability and individual heritability were ranged from 0.284 to 0.797 and from 0.048 to 0.483, respectively. The results of correlation analysis showed that the correlation of almost all traits reached a significant level (P < 0.05), except the correlations between sharpness and branch angle, between sharpness and number of side branches, and between straightness and crown width. The results of general combining ability analysis showed that with a selection rate of 20%, 6 excellent parents were screened according to different traits. The results of principal component analysis (PCA) showed that the cumulative contribution rate of the three principal components reached 73.264%, indicating that the three principal components contained most information of the measured trait. According to the comprehensive scores of PCA, one excellent provenance, three excellent families and 10 excellent individual plants were initially selected. The realistic gains of tree height, average annual increase in tree height, ground diameter and crown width of selected provenance were 3.109%, 5.014%, 2.193%, and 1.040%, respectively. The genetic gains of the 4 traits of the families selected were 5.835%, 5.410%, 7.908%, and 6.069%, respectively. The genetic gains of the 4 traits of selected individuals were 26.74%, 24.11%, 23.91% and 26.53%, respectively. Conclusion The growth traits of J. mandshurica have rich variations within provenances and families. The excellent provenances, parents, families and individuals preliminary selected could lay a basis for the selection and application of J. mandshurica varieties.