Here, we describe an interesting case of a 67-year-old woman who suffered from hypercalcemia with nephrocalcinosis and nephrolithiasis caused by a novel finding of the simultaneous presence of pHPT as a frequent cause, and a novel combination of two pathogenic CYP24A1 mutations as a very rare cause of hypercalcemia. Here, CYP24A1 is linked to hypercalcemia disease.