Primary squamous cell carcinoma (SCC) with sarcomatoid differentiation of the kidney was rarely reported. This disease is usually related to renal stones, and due to a lack of symptoms and radiological features, patients usually attend the hospital with late stage disease.A 54-years-old female presented with left flank pain and an abdominal mass for 6 mo. Imaging studies revealed that the left kidney was enlarged and massive hydronephrosis was present. A stone was seen in the ureteropelvic junction. The patient subsequently underwent left radical nephrectomy, and histopathological examination of the mass revealed a poorly differentiated renal SCC with sarcomatoid differentiation. After primary surgery, the patient received four cycles of tirelizumab. Four months later, the patient developed adrenal, lymph, and uterine appendage metastases.SCC of the kidney has a poor prognosis, and should be considered in patients with a renal mass, long-standing urinary calculi and massive hydronephrosis.©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.