Secondary (renal) hyperparathyroidism appears in chronic renal failure, sometimes in patients on chronic dialysis. Other causes includes rickets and osteomalacia. These diseases are associated with poor calcium and vitamin D absorbtion from the small bowel. Two patients with chronic renal failure maintained on chronic haemodialysis from two and three years, respectively underwent subtotal parathyroidectomy: removal of three glands and preserving a half of a gland in situ. The diagnosis and surgical indication was made upon clinical (bone pain and severe itching), radiological (demineralisation, ectopic calcifications) and biochemical (hypercalcemia, hyperphosphoremia, increased values of alkaline phosphatases) arguments. Postoperatively the improvement is defined by a return to normal in the clinical, laboratory and radiological parametres. The most appropriate operation for secondary hyperparathyroidism is still unresolved one of two techniques is performed according to the preference of the surgeon: subtotal parathyroidectomy or total parathyroidectomy with autotransplantation of parathyroid fragments into forearm muscle.