Abstract: The aim was to research genetic relationship of quantitative traits with doubled haploid populations in Brassica napus L. These quantitative traits included plant height, branch height, first effective branch number, main inflorescence pod number, biological yield, economic yield and thousand seed weight. Through phenotypic analysis, partial correlation analysis, heritability, the least gene pairs estimate and gene interactions to analyze quantitative traits data of DH group and its parents. The results showed that: branch height, main raceme length, pods number of main raceme and single plant biological yield were partial to male parent, but the first effective branch number were partial to female parent. Plant height, economic yield and thousand seed weight were transgressive inheritance. Majority character showed extremely significant positive correlation, but between branch height and first effective branch number, main raceme length and the first effective branch number, pods number of main raceme and the first effective branch number showed extremely significant negative correlation. The maximum of branch height heritability was 83.31% and the minimum of thousand seed weight heritability was 60.9%. The least gene pairs of controlling each character was13.8, 12, 23, 12.5, 24.7, 20.9, 11.1 and 13.8, respectively. According to estimated coefficients of skewness and kurtosis of the traits tested, the gene of control plant height and branch height were not interaction; gene of control first effective branch number existed interaction effect. There could be gene interaction were found for the pod number of main raceme, biological yield and thousand seed weight. The duplicate interaction was observed for the length of main raceme and economic yield.