In spite of essential enrichment of our pathophysiological knowledge in the field of the calcium-phosphate metabolism and bone alterations in renal transplant patients, both diagnosis and therapy of these abnormalities still remain a challenge for nephrologists and transplantologists. The present study aimed to establish the diagnostic value of traditional and contemporary markers of Ca-P metabolism and bone alterations in kidney transplant patients 4 or more years after Tx and the main factors responsible for osteodystrophy after Tx respectively. 61 patients and 21 controls were examined. The assessed parameters were: serum levels of total (Ca) and ionized calcium (Ca2+), serum concentration of phosphorus (P), intact PTH, calcitonin, osteocalcin, 25-OH-D3, collagen type I cross-linked C-telopeptide and activity of alkaline phosphatase (total and bone isoenzyme). In all subjects bone densitometry of the total body, L2-L4 vertebrae and femoral neck were performed. In kidney transplant patients routinely assessed markers of calcium-phosphate metabolism (Ca, Ca2+, P, alkaline phosphatase total and bone fraction) were in the normal range while significantly elevated serum concentrations of PTH, osteocalcin and CTx were found. In more than 20% of renal transplant patients osteoporosis and in further 50% patients osteopenia were found by DEXA. The intensity of bone abnormalities was dependent on the duration of dialysis therapy before Tx, time after Tx, degree of impairment of the graft, intensity of hyperparathyroidism and total dose of corticosteroids. From results obtained in this study estimation of serum concentration of 25-OH-D3, PTH, CTx and the BMD respectively is mandatory to detect Ca-P abnormalities and osteoporosis or osteopenia in Tx patients.