Objective To evaluate the effectiveness and safety of sacral neuromodulation for the treatment of painful bladder syndrome/interstitial cystitis. Methods There were 21 painful bladder syndrome/interstitial cystitis patients treated during April 2012 to October 2014. Behavior therapy, oral therapy, intravesical instillation of sterile sodium hyaluronate, water expansion of bladder, bladder submucosal injection of botulinum toxin type A and so on did not have a good effect on the patients. The data of voiding diary, visual pain scale, interstitial cystitis symptom index and quality of life score were collected. The time of follow-up was 2 week, 3 month and 6 month after the surgery. Then the patient was followed up every 6 months.Those individuals demonstrating a 50% reduction in voiding diary, visual pain scale, interstitial cystitis index and the quality of life score were eligible for surgical placement of a permanent device. Results Three of them refused to accept InterStim therapy because of failure of experimental therapy. Eighteen of them received InterStim long term implantation therapy. The rate of long term implantation was 86%. The average follow-up time was 18 months. Before the surgery, the average voiding times of 24 hours, the times of nocturia, the voiding volume, the visual pain score, the interstitial cystitis problem index, interstitial cystitis symptom index and the quality of life score were 23.2±7.1, 13.0±4.7, 73.3±12.9 ml, 7.2±1.1, 15.6±1.3, 14.1±1.8, 5.6±0.5. After surgery, the data were 11.1±3.2, 5.9±2.1, 164.4±28.5 ml, 3.4±0.8, 7.0±0.7, 6.6±1.0, 1.9±1.0, respectively. And there were significant differences (P<0.05). There was no complication such as infection, electrode displacement, electrode fracture and so on. Conclusion Results of this initial clinical study demonstrate that sacral neuromodulation is safe and effective for refractory painful bladder syndrome Key words: Sacral neuromodulation; Urination disorders; Urine control; Cystitis, interstitial; Painful bladder syndrome