Objectives: To characterize primitive neuroectodermal tumor of the kidney as a differential diagnosis for Wilms tumor, and to emphasize the severity of the disease. Methods: We report the case of a patient with a diagnosis of primitive neuroectodermal tumor of the kidney who underwent nephrectomy and complete tumor resection combined with chemotherapy. Results: At the beginning, the patient had a favorable outcome, with few problems, especially related to the agranulocytosis. After ten months of the end of treatment the patient had a relapse at the paraspinal cervical region and abandoned the treatment. Conclusions: The primitive neuroectodermal tumor located in the kidney is very rare and also very aggressive. The role of the pathologist is fundamental for the characterization of the disease: using histological and immunohistochemical methods, he provides the final diagnosis.