Abstract: The plantlet regeneration from Cotyledon of Citrullus lanatus was studied. The results showed ：The most suitable medium for buds induction from cotyledon of Citrullus lanatus was MS＋6-BA 3.0mg/L＋NAA 0.1mg/L. The buds induction of the cotyledon should be started in darkness and its further growth and differentiation must be carried out in light. The optimum rooting media were 1/2MS＋IAA 0.4mg/Land 1/2MS＋IBA 0.3mg/L.The research established preliminarily a system of genetic transformation and quick propagation for cotyledon of Citrullus Lantus.