OBJECTIVE To prevent early closure of growth plate and developmental deformities of limbs by allografts of cultured cartilages into growth plate defects of rabbits. METHODS Chondrocytes isolated from articular cartilage of 1-month rabbits formed cartilage after cultivation in centrifuge tubes. The cartilages cultured for two weeks were implanted into growth plate defects of proximal tibiae of 6-weeks rabbits. At 4th and 16th weeks, X-ray, histologic and immunohistochemical examination were performed. RESULTS The tibiae had no marked deformities after 4 weeks of operation. Histologic examinations showed that the defects were filled with cartilage. Immunohistochemical results of type II collagen were positive. The tibiae with allografts of cultured cartilages had no evident deformities after 16 weeks of operation. Histologic examination showed nearly closure of growth plates. On the contrary, the tibiae on control side formed severe deformities and growth plate were closed. CONCLUSION Allograft of cultured cartilages into growth plate defects may replace lost growth plate tissues, maintain normal growth of limbs and prevent developmental deformity.