In this study we presented 92 cases with regional lymphadenitis (over 1 cm in diameter) which was caused by BCG vaccination generally performed a few days after birth. The patients were divided into four therapy groups. In group I, the lymphadenitis in 26 cases was excised totally by a surgical operation and they improved in a median period of four weeks (average: 4.4). No therapy was applied in 33 patients constituting group II and their periods of improvement were 28 weeks (average: 29.1). Sixteen cases in group III were given isoniazid (INH) 10 mg/kg for six months in addition to total surgical excision and their healing period was 4.5 weeks (average: 4). Seventeen cases in group IV were administered only INH for six months and the median improvement period was found to be 27 weeks (average: 28.2). The statistical differences in terms of the improvement periods between groups I and III, and groups II and IV were found to be insignificant (p > 0.05) but these differences were significant between groups I and II, groups I and IV, groups II and III, and groups III and IV (p < 0.05). These results show that spontaneous healing is possible. Total excision is the best therapy for BCG lymphadenitis in suppurative forms and INH has no effect in shortening the therapy period.