Osteoporosis remains a major problem following kidney transplantation. Radiographic measures of bone mass have limited predictive value after transplantation and are complicated by preexisting renal osteopathy. Quantitative ultrasound (QUS) is a noninvasive method to assess bone status. However, limited data exist on changes of ultrasonic parameters of phalanx after transplantation. We evaluated the potential use of this method in renal allograft recipients and compared the results with that obtained from normal age-sex matched controls. Forty-two renal transplanted patients (22 women), with mean age of 40.17 +- 11.9 years, studied 2.8+- 2.9 years after transplantation. Forty-nine age and sex matched, healthy persons used as controls. A Lunar device (DPM-MD) used for DXA scanning and QUS of phalanx was done by a DBM-Sonic 1200 device. Mean of Ad-SOS (amplitude dependent speed of sound, the parameter measured in QUS of phalanx) was 2036+- 79 in patients and 2060+- 86 in controls. There was no significant difference between them. Age, BMI (negatively) and height (positively) were significantly related to Ad-SOS in patients (P-values, 0.027, 0.001 and 0.013, respectively). There was no significant relation between Ad-SOS and weight, dialysis time, time after transplantation, steroid and cyclosporine cumulative doses. Our data suggests that phalanx QUS is not a good way for assessing the changes of bone in renal transplanted patients in comparison to healthy persons, but may it can be used for screening of osteoporosis in such patients. For establishment of diagnosis, patients must be examined with DXA.