Abstract: In this experiment the synchronization regulation of somatic embryogenesis from the embryogenic callus were performed in Dimocarpus longan Lour. cv. Honghezi and the somatic embryos at heart-stage, torpedo-stage and cotyledonary-stage were obtained. The results showed that the developmental synchronization of somatic embryos at heart-stage and torpedo-stage could be roughly achieved by changing the concentrations of 2,4-D in the media gently at the middle developmental stages during longan somatic embryogenesis.