Objectives: Transcutaneous Tibial Nerve Stimulation (TTNS) is a non-invasive method used in OAB treatment. We aimed to compare the effectiveness of the once a week and three times a week TTNS procedure in women diagnosed with wet type refractory OAB. Methods: A total of 60 patients diagnosed with wet type OAB was refractory to medical treatment included in the study. Participants were equally and randomly divided into two groups: TTNS treatment was performed with a time duration of 30 minutes for 12 weeks, once a week to Groıp-I and three times a week to Group-II. Pre and post-treatment OAB-V8/ICIQ-SF scores and voiding frequencies recorded in the bladder diary were compared between groups. Results: Four patients in Group-1 and eight in Group-2 left the study without completing the treatment. TTNS was performed in both groups for 12 weeks. There was a significant decrease in the voiding frequency, OAB-V8, ICIQ-SF scores in both group-1 and group-2 (p<0.001). A significant decrease in the OAB-V8 score was observed in the 5th week in Group-1, and on the 3rd week in group-2. Complete response was observed in 6 patients (23.1%) in Group-1 after 12 weeks of TTNS procedure. In group-2, 10 patients (45.5%) had a complete response. After the 12-week TTNS procedure, no significant difference was observed between the groups in terms of treatment response. Conclusion: TTNS can be safely used before invasive treatments in resistant OAB. TTNS procedure three times a week seems more effective than performing it once a week.