INTRODUCTION: Overactive bladder syndrome is defined by The International Continence Society as urgency, with or without incontinence, usually with increased urinary frequency and nocturia. It is difficult to estimate the prevalence of this syndrome because many patients do not seek medical help, despite considerable negative impact on quality of life. Lower urinary tract dysfunctions can be treated using electrical stimulation of the posterior tibial nerve. This therapy is conservative, effective, inexpensive and promotes high adhesion to treatment. It has good results, decreasing symptoms of urgency, urge-incontinence, urinary frequency and nocturia . Due to lack of consensus on the parameters of this technique, further research is necessary. OBJECTIVE: To compare the effectiveness of protocols for the electrical stimulation of the posterior tibial nerve for treatment of non-neurogenic overactive bladder. METHODS: The study was a blind randomized clinical trial. The study will accept up to 145 women with overactive bladder diagnosis for at least six months prior to the beginning of the study. The subjects will be divided into five groups: group 1 (placebo group), group 2 (electrical stimulation of one leg once a week), group 3 (electrical stimulation of one leg twice a week), group 4 (electrical stimulation of two legs one a week) and group 5 (electrical stimulation of two legs twice a week). Physical evaluation will be done at the beginning and at the end of the treatment. Evaluation will be done using the King "s Health Questionnaire, the International Consultation Incontinence Questionnaire - Short Form, the Overactive Bladder Questionnaire, a three day urinary diary and a table for follow-up treatment.