Persistently high frequency of forearm fractures in frontal and side impacts coupled with their longterm deleterious effects demands an in-depth understanding of variation in skeletal response to loading. Previous work has highlighted the differential impact of subject-level variables on bone quality between males and females. The purpose of this study was to evaluate effects of sex on variation in cortical bone morphometrics of the radius. Quantitative computed tomography analyses were performed on n=150 ex vivo post-mortem human subject radii from 96 males and 54 females. Morphometrics that represent bone quantity, cross-sectional distribution, whole-bone geometry, and mineralisation were quantified in the radius diaphysis. Females demonstrated significantly smaller cortical morphometric parameters (p<0.003) with the exception of wholebone geometry and mineralisation (p>0.81). Sex-specific linear regressions demonstrate significant increases in some parameters with age in males (p<0.004) however, the amount of bone and mineralisation decreased with age in females (p<0.001). Females appeared to be more sensitive to changes in height and demonstrated positive relationships in more morphometrics than males. Multivariate regressions analysing combined effects of age and height explained more variation in morphometrics than age or height alone. The sex-specific effects of subjectlevel variables on cortical bone indicate varying mechanisms of bone functional adaptation that should be accounted for in injury risk predictions rather than body size-based scaling techniques.