It is difficult to manage the growing deformity of forearm bone caused by hereditary osteochondromatosis in children, because deformity and discrepancy of limb length is progressive. The are many treatment methods of these problems including excisio of osteochondroma, lengthening of ulna, shortening of radius, corrective osteotomy with or without lengthening apparatus. Among many treatment methods, we tried free vascularized epiphyseal transplantation with the proximal fibular epiphysis in 3 patients of hereditary osteochondromatosis for inducement of continuous bone growth and deformity correction. The average duration of follow up was 7 years and 1 month, the shortest duration being to 4 years and 5 months and the longest 10 years and 8 months. Serial radiologic and clinical evaluation were carried out during follow up and there were satisfactory length gain, deformity correction and improvement of adjacent joint motion in 2 cases. According to our follow up evaluation, free vascularized epiphyseal transplantation is valuable procedure in forearm deformity of hereditary osteochondromatosis although it needs skillful and experienced operative technique.