Primary small cell neuroendocrine carcinoma (SCNEC) is a rare high-grade malignant neoplasm with neuroendocrine differentiation derived from the urothelium. Herein, we report a case which presented with symptomatic anaemia secondary to haematuria, complicated with acute kidney injury following obstructive uropathy caused by the SCNEC, along with the discussion of the clinical presentation, radiological imaging and pathological findings of the disease.