AIM: Various surgical and minimally invasive treatment options are available in the treatment of pilonidal sinus. In our study, we aimed to retrospectively analyze the results of crystalline phenol application in patients who applied to our clinic with pilonidal sinus. MATERIAL AND METHOD: Patients who were applied crystalline phenol due to pilonidal sinus disease between 20182019 were included in the study. The patients were evaluated in terms of demographic characteristics, pit count, surgical treatment history, abscess drainage history, number of repeated applications, complication status, recovery rate in the first month, success rate in the first year, and recurrence. RESULTS: 209 patients participated in our study. The average age of patients was 25.5, and the number of male patients was 4 times that of women. The patients had an average of 2.13 pits. Twenty-two patients had a history of abscess drainage. Thirteen patients had a history of surgical treatment. The recovery rate was 89.3% in the 1-month controls and 93.7% in the 1-year controls. Repeated application was performed to 11% of the patients. Seventeen patients had recurrence after wound healing. The most common complications were skin burn (1.4%) and wound infection (1.4%). CONCLUSION: In the treatment of pilonidal sinus disease, crystalline phenol can be safely applied with a high success rate, low recurrence rate and an acceptable percentage of complications.