Abstract： Objective To evaluate the postoperative bladder function by urodynamic studies in children with bladder rhabdomyosarcoma (RMS) so as to guide the clinical rational drug use,facilitate the training of bladder function,promote the recovery of bladder function and reduce the complications.Methods The voiding diary and clinical data of 12 children patients with bladder RMS were collected and urodynamic studies performed from August 2003 to August 2013.According to the urodynamic results,bladder function training was conducted,including pelvic floor muscle and toilet training.The relevant influencing factors of bladder function were analyzed.Results A total of 12 children with bladder RMS was treated and postoperative urodynamic studies were performed routinely.Except for one mortality,the remainder had event-free survival.Urinary continence was preserved in 9 cases with diurnal urination intervals between 1-3 hours and nocturnal urination at 0-2 times.Stress urinary incontinence occurred in 1 patient with diurnal urination intervals between 30-40min and nocturnal urination at 2-3 times.The last one received bladder function training.The final urodynamic results,including bladder pressure,maximum cystometric capacity (MCC),residual urine volume,flow rate and bladder compliance of 9 cases were all normal after the final chemotherapy course.One case of stress urinary incontinence improved by bladder function training.MCC was approximately 135 ml (90％ of minimal calculated bladder capacity) and residual urine volume,bladder pressure and flow rate were all normal.MCC and bladder compliance decreased in one child for 6months after operation and the child underwent training.Conclusions After operation,there is no obvious adverse effect on bladder function in children with bladder RMS on chemotherapy.Urodynamic studies may accurately evaluate the postoperative bladder function,guide functional training and clinical medication and improve bladder function.