Effects of ultrasonic frequency, the processing time as well as the solid-liquid ratio on the extraction of dioscin were investigated, also selected proper surfactant and usage for ethanol extraction, and using electrical conductivity method determinate the critical micelle concentration, finally obtained an optimization process by orthogonal experiments. The results showed that the best extraction conditions were: ethanol volume fraction was 30%, ultrasonic frequency was 25.8kHz, ultrasonic time was 40min, solid-liquid ratio was 1:10, sodium lauryl sulfate(SDS) usage was 17.408?0-3mol/L. The process can significantly increase yield, saving time and energy, reduce pollution, has a great feasibility in industry promoting.