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The human brain is sexually dimorphic and these sex differences have shown to affect brain response to trauma. We investigated the sex differences in the tract structures by studying diffusion weighted (DW) images of 594 females and 506 males from the Human-Connectome-Project dataset. All the female and male DW images were reconstructed in the ICBM152 space using Q-Space diffeomorphic reconstruction technique and their mapped orientation distribution function images were averaged to generate the female- and male-DW-templates. The tract streamlines were generated through tractography for female and male templates and normalized to the total brain volume . The distributions of normalized tract lengths were significantly different between female- and male-templates and the female-template showed to have more longer normalized tracts compared to the male template. For the regional analysis, the templates were parcellated into sixteen regions of interests (ROI) including brain-stem, five subregions of corpus-callosum, and right and left hippocampus, thalamus, cerebellum white-matter (WM), cerebral WM, and cerebellum cortex using a FreeSurfer-based segmentation atlas. For all the ROIs, the average fractional anisotropy (0.5-5.7%) and normalized tract lengths (1.1-2.7%) were larger in female template while the average mean diffusion was larger (1.3-5.6%) in male-template. Quantifying brain connectivity by counting number of tracts passing through pairs of ROIs, showed more pairs with a higher connectivity in female-template, and one of the highest percentages of sex differences in right/left cerebellum WM/cortex connections. Our results reinforce the need to continue investigating the sex variations in axonal structure and their effects to brain trauma.