The aim of this study was to investigate a morphometry (bone mass), densitometry (mineral content, mineral density measured using dual energy X-ray absorptiometry (DXA) method), geometry (cortical wall thickness, cross sectional area, cortical index) and bone strength in weaned female piglets growing from 56 to 115 day of life and differed in body fatness understood as fat : lean mass ratio established using DXA. Correlations between measured properties and body fatness were also considered. Sixteen 56-day old cross-breed piglets were allotted into two experimental groups (8 animals in each): thin – T (fat : lean mass ratio <0.12) and fat – F (fat : lean mass ratio >0.12), based on fat : lean mass ratio in the body. Both groups of pigs were fed the same diet ad libitum (13.5 MJ · kg^-1 metabolizable energy, 10.5 g of digestible lysine per kg). At 115 day of life the T animals had heavier bones (P < 0.01), higher bone mineral content (P < 0.01), higher bone mineral density (P < 0.05), higher cortical wall thickness (P < 0.01) and cross sectional area (P < 0.01) in comparison to F pigs. Bone strength and cortical index did not differ between groups. Body fatness was negatively correlated with: bone weight (r = −0.55, P = 0.001), bone mineral content (r = −0.52, P = 0.001), bone mineral density (r = −0.27, P = 0.029), cortical wall thickness (r = −0.38, P = 0.002) and cross sectional area (r = −0.57, P < 0.001). Correlations with bone strength and cortical index (relative proportion of cortical bone to total periosteal breadth at midshaft) were insignificant.