Urine calcium-creatinine ratios (UCa/UCr) in 930 elementary school children in Van were determined to find out the epidemiology and etiopathogenesis of hypercalciuria in children. At least two determinations of calcium-creatinine ratios above 0.21 were accepted as criteria for hypercalciuria. Those who fit the hypercalciuria criteria were further examined. The hypercalciuria incidence in our area came out to be 6.23%. Seventeen of the 58 hypercalciuric children could be examined thoroughly. Although of those children had a family history of urolithiasis, the x-ray and laboratory examinations revealed no urinary stone, urinary infection or metabolic disorders.