Calcinosis cutis is characterized by the deposition of calcium salts in the skin and subcutaneous tissue. It is divided into the following subtypes: dystrophic, metastatic, iatrogenic, idiopathic and calciphylaxis. In this case, we report a 13-year-old Syrian boy with idiopathic calcinosis cutis, the lesions were unusually widespread, unlike the common condition which is usually localized to one area. The case was unrelated to any systemic or local disorders, and the patient had no complications, so no treatment was planned.As the best of our knowledge, there are very few cases of diffuse or widespread idiopathic calcinosis cutis. We analyzed the clinical, laboratory, radiographical and pathological characteristics of our patient, which helped us to reach the final diagnosis. We will discuss the pathogenesis, investigation and management of this disease.