Since October 1994, we have been treating adult groin hernia according to the concept of tension free hernioplasty that was advocated by Lichtenstein. In this study, 61 tension free hernioplasties (including 43 mesh plug repairs and 18 laparoscopic hernioplasties) were compared with 49 conventional hernioplasties which were performed from January 1991 to December 1994. There was no significant difference in the mean hospital stay, but the tension free hernioplasty was significantly superior to the conventional method in postoperative pain and recurrence rate. Especially mesh plug repair permits to approach with the same knowledge as the conventional hernioplasty demands; does not need such special technique as laparoscopic surgery requires; does not require general anesthesia; shortens the operating time; and saves the medical cost. This mesh plug repair that is minimal invasive procedure in tension free hernioplasty will be a standard operation for adult groin hernia.