This prospective study evaluated the accuracy of grey-scale two-dimensional (2D) ultrasonography and real-time three-dimensional (3D) ultrasonography-based virtual cystoscopy for detecting early recurrence of bladder cancer in previously treated patients (n = 40). Real-time 3D ultrasonography-based virtual cystoscopy images were compared with both 2D ultrasonography and interval conventional cystoscopy pathology results. Ultrasound examinations were performed before routine follow-up with conventional cystoscopy. Overall sensitivity for real-time 3D ultrasonography-based virtual cystoscopy was lower than for 2D ultrasonography, indicating it did not provide additional information. The results of combined (2D and 3D) ultrasonography and conventional cystoscopy differed significantly. Where lesions were detected with combined ultrasonography, the number of previous cystoscopies was lower and the tumour stage was significantly higher at initial diagnosis, compared with cases where no lesions were detected. The results suggest that ultrasonography before cystoscopy can be performed more frequently - or, if no lesions are detected by ultrasonography, the interval between cystoscopies can be prolonged - in patients at high risk of bladder cancer recurrence.