Purpose:Recent studies showed that sacral nervestimulation might be an effective treatment option forchronic anal fissure. We aimed to evaluate the efficacy oftranscutaneous electrical nerve stimulation as a noninvasivealternative treatment for chronic anal fissure bystimulating the sacral nerve in the ankle via the posteriortibial nerve. Method: In this prospective study, transcutaneouselectrical nerve stimulation was applied for 20 minevery day for 5 days in a week, for a period of 2weeks in addition to conventional medical treatment intwenty patients. Wexner\'s constipation score, visualanalog scale for pain, symptom relief, compliance,fissure healing, and side effects were evaluated before andafter treatment (days 0, 10, and 30). Results: Twenty patients (fifteen females/five males) witha mean age of 34.75?11.42 years were enrolled in thestudy. The improvement of symptoms after the fifth dayof treatment was seen in 5 patients, and mucosal healingwas observed in fourteen patients 30 days after thetreatment. Wexner\'s constipation and visual analog scalescores for pain decreased significantly (p=0.000 andp =0.000, respectively). Two patients underwent surgeryat follow-up due to persistence of symptoms, andlateral sphincterotomy was done. Conclusions: Transcutaneous electrical nerve stimulation applicationto the posterior tibial nerve has the potential to bean alternative treatment option for chronic anal fissure patientswho seek noninvasive treatment modality.