Abstract: The callus of Tripterygium wilfordii was used to study the effect of basic media,different plant growth regulators and different concentrations of growth regulators on regeneration of T. wilfordii. And the process of the somatic embryogenesis was observed. The results showed that NAA was more effective auxin than 2,4-D in inducing the plantlet regeneration of T. wilfordii. Cytokinins could promote the callus differentiation,for which 6-BA was more effective than KT. The combination of NAA and 6-BA encouraged more regeneration than each of them used alone. Among the 6 media supplied,MS and B5 brought about 100% regeneration rate for callus. On MS medium supplemented with 0.1 mg·L^-1 NAA+1.0 mg·L^-1 6-BA,the callus had 100% regeneration rate,and each callus had relatively more shoots on average than other combinations. Histological observation showed that a somatic embryogenesis of T. wilfordii originated from a single cell of the internal of callus and its development procedure was similar to that of a zygotic embryo.

Key words: Tripterygium wilfordii, callus, somatic embryogenesis, plantlet regeneration