Intradiverticular bladder tumours (IDBT) account for approximately 1% of all urinary bladder tumours. The risk of developing a tumour within a bladder diverticulum is considered to be greater than in the main bladder, possibly owing to prolonged contact of potential carcinogens with the mucosal lining from urinary stasis. Patients with these tumours most commonly present with visible haematuria. Diagnostic tests include urine cytology, cystoscopy, ultrasonography, CT, MRI, and biopsy. Lack of muscle in the diverticula increases the risk of bladder perforation during biopsy and makes pathological staging difficult as there is no T2 stage; instead, data suggest that any invasion beyond the lamina propria should be described as T3. IDBT can be managed by transurethral resection and adjuvant intravesical therapy, diverticulectomy, or cystectomy (partial or radical), as outlined by the only guidelines to specifically address the management of IDBT, which were published by the Cancer Committee of the French Association of Urology (CCAFU) in 2012. The prognosis of patients with intradiverticular bladder tumours has always been perceived to be worse than those with intravesical tumours; however, the only study of 5-year survival rates for patients with IDBT suggests that prognosis might be comparable for these conditions.