Abstract: The optimal extraetion teehnology of caulerpin from feathery fern frond was studied by mierowave assisted extraetion. The effect of the microwave temperature, ethanol concentration, the microwave extraetion times, the microwave power and the ratio of solid to liquid on the yield of caulerpin were studied by single factor experiments. Then, the optimal processing conditions of caulerpin were obtained by the orthogonal experiments. The optimal extraction process parameters include 90% ethanol as extraction solvent, microwave temperature of 50℃, microwave power of 300 W, microwave radial time of 15 min and material-liquid ratio of1∶40g·mL-1. Under the optimal extraction conditions, through duplicated experiment the yield of caulerpin was92.93%, RSD was 0.5003%. The results showed that microwave extraction rate was extremely high and stable, and the extraction time was reduced greatly at the same time.