The aim of the study was to evaluate result of non-surgical treatment among adolesecent and adult cases.Material and methods. This study was carried out on cases with umbilical pilonidal disease who refused surgical treatment as first line treatment. Duration of study was from 2003 to 2006. If a patient due to complication required surgery, was not excluded from study. Data was analyzed by SPSS ver 13.0 (Chicago, IL, USA).Results. In this study, 51 cases were included. Mean ± SD in male was 23.57±6.11 (range 16-40) and female was 27.93±11.38 (range 15-60). Patients were divided in two groups. Group 1 included cases ≤25 yrs and consisted of 32 cases. Cases >25 yrs were placed in group 2 (19 cases). From 51 cases included in this study, 43 of them were appropriate for non-surgical treatment. Eight cases underwent surgical treatment. Of 51 cases, 35 cases (68.6%) were male and 31.4% were female. Of 43 cases who treated conservatively, 29 (67.44%) cases were male and 14 (32.56%) were female. There was no significant difference between rate of successful conservative treatment among cases >25 yrs and cases ≤25 yrs. There was no significant different between different duration of manifestation.Conclusion. In this study we found successful non-surgical treatment in 90.6% of cases ≤25 yrs and 73.7% of cases >2 yrs. Non-surgical treatment may be appropriate option in uncomplicated cases. Another study is recommended to confirm this method of treatment.