Melanosis vesica is a rare condition and thought to be benign. We report the case of a 50-year-old man who presented with haematuria and was found to have a diffusely pigmented bladder on cystoscopy and high grade transitional cell carcinoma of his upper and lower renal tract. This required a laparoscopic nephroureterectomy and pathology confirmed a diagnosis of melanosis vesica. Melanosis vesica has only been associated with high grade transitional cell carcinoma in one previous case. We recommend that any patient presenting with bladder melanosis is monitored for the development of upper or lower urinary tract transitional cell carcinoma.