Post-transplant hypercalcemia due to persistent secondary hyperparathyroidism (HPT) has a high prevalence in the first 3 months after surgery and decreases during the first year, but it persists over time in around 5-10% of renal transplant patients. The increased bone resorption and tubular reabsorption of calcium due to the action of the parathyroid hormone (PTH) appear to be the main mechanisms involved in hypercalcemia. At the time of the renal transplantation (RT), PTH is the factor that determines the development of post-RT hypercalcemia, although it is sometimes masked in patients who are well controlled with medical treatment. The number of dialysis patients receiving treatment with cinacalcet for secondary HPT is increasing. The withdrawal of the calcimimetic at the time of renal transplantation results in a higher prevalence of hypercalcaemia and hyperparathyroidism in these patients. In patients with PTH well controlled with cinacalcet before transplantation, there is a direct relationship between the dose and the subsequent development of hypercalcemia, probably because it indicates the presence of a more severe secondary HPT. Hypercalcemia may have deleterious effects on the renal graft, resulting in tubulointerstitial calcification. Persistent hypercalcemia is a marker of an increased risk of bone disease deterioration in these patients. Nowadays, the first treatment option is cinacalcet and if there is no response, we consider performing a parathyroidectomy. In this review, we propose an algorithm for management of post-RT hypercalcemia.