Abstract: This paper represented the synchronization of somatic embryogenesis of Coptis chinensis F. by using physical and chemical methods as well as a comprehensive method——plant growth regulators supplemented with fractional sieve. The results have shown that the comprchensive method was thebest one compared with the physical or chemical methods. The somatic embryos of C. Chinensis were induced on basal MS medium containing 0.5mg/L 2,4-D+0,2mg/L NAA, then transferred into the MS medium supplemented with 0.5mg/L ABA+0.2mg/L NAA subcultured for two weeks. After the somatic embryos fractionated with different mesh size of sieves, 60—85% of synchronous rates of somatic embryos were achieved in this method. From this study, we can get a conclusion: the key point in plant somatic embryogenesis and synchronization is to control the development of somatic embryos by using correct kinds of and suitable concentrations of plant growth regulators. To use fractional sieve is only a method for getting identical size of somatic embryos.