To evaluate the association between quantitative ultrasonography at hand phalanges (QUS) and dual energy X-ray absorptiometry (DXA), and between these methods with food intake and history of bone fractures. After two years of follow up of 270 schoolchildren, 10 of them, who showed bone mass below - 2 SD in QUS, were included in the present study. Laboratory results and DXA data were analyzed. Bone mass evaluated by DXA at L1-L4 ranged from -2.8 to -1.1 SDS, and whole body bone mass, from -2.9 to -1.2 SDS. Three children had history of non-pathological bone fractures. Dietary assessment showed low intake of calcium in 10 cases, of phosphorus in 6, and of vitamin D in 8 cases. There were no differences among the cases of bone mass below-2 SD in any of the three used methods. There was no association between history of bone fractures and food intake, and between these evaluations and bone mass. In this small group of schoolchildren there was an association between the methods QUS and DXA. However, there was no association between bone mass and the history of bone fractures, or calcium, phosphorus and vitamin D intake.5619-24