Leukoplakia of the bladder is a rare condition. It is characterized by squamous metaplasia of the transitional epithelium and keratinization. The etiology and possible pathogenetic factors are discussed. Up to 42% develop carcinoma which makes early diagnosis important. The clinical diagnosis is difficult. The patients present with symptoms of vesical irritation and the passage of flakes is pathognomonic. Diagnosis is made by cystoscopy with biopsies. Characteristic cystoscopic findings are described. Treatment and a follow-up programme are outlined. As conservative treatment remains unsatisfactory radical extirpation or cystectomy is recommended for extensive lesions.