One case of massive osteolysis Gorham-Stout is presented. Idiopathic osteolysis is a rare disease. The coincidental radiological diagnosis following minor trauma or a few months' history of mild pain involving joints is characteristic. The disease process has a sudden onset. Bones undergo partial or complete resorption, which may spread across joints to contiguous bones. The osteolytic process eventually ceases spontaneously, but generally not before severe deformation and destruction of bone has occurred. Usually radiotherapy is not successful and is followed by local resection of the osteolytic process. Based on our presented case, we suggest early operative treatment to prevent severe damage.