Regional lymphadenitis is the most common complication following BCG vaccination in this country. The literature describes controversial results with medical, surgical and combined therpy. The purpose of this study is to clarify the therapeutic effect of isoniazid(INH) after surgical procedures. The early and late postoperative complications of 136 children with lymphadenitis following BCG vaccination at the Taegu Fatima Hospital between March 1985 and February 1996 were reviewed. In 90 children, INH was given for 3-4 days before operation and for 3 months after surgery. In the other 46 cases, INH was not given during the pre- or postoperative period. Surgical procedures were excision or incision and currettage according to the states of lesions. Postoperative complications were fluid accumulation, wound infection, sinus formation and others. Complication rates were 14.4 % in INH-treated group and 13.0% of INH-nontreated group. The difference was not significant. There was no recurrence or other late complication in either groups. The result suggest that surgical excision or incision and currettage are sufficient for the treatment of regional lymphadenitis following BCG vaccination and postoperative INH therapy is not necessary.