This study includes all the children treated with OK-432 for lymphangioma at our institute. Twenty-nine children treated between 1999 and 2003 are reported for the first time: twelve cases regressed completely, eight cases regressed more than 50% and seven remained unchanged; two cases were lost at follow-up. The outcome was related to the size of the cysts, the larger ones having a better prognosis. The adverse reactions are discussed and the methods of treatment are described in detail. Fifteen children, treated before 1999 and already reported, are reviewed after a long-term follow-up. Four had a recurrence: one regressed spontaneously and three needed further treatment. The other 11 had no complaints. Even considering the risk of recurrence, OK-432 therapy remains our first line therapy for lymphangiomas, avoiding surgery in most cases.