Abstract: Flash extraction was used to extract the ergosterol from Lentinula edodes stipe.The extraction process was optimized and the results were compared with those of conventional reflux extraction and ultrasonic extraction. The effects of three factors such as liquid- solid ratio, extraction time, extraction voltage on ergosterol extraction yield were studied by orthogonal method.The optimum extraction conditions were as follows: liquid- solid ratio 20mL /g, extracting 4min, voltage 100V, under the conditions the extraction yield of ergosterol was 2.762mg /g, compared with other two methods, flash extraction had the remarkable superiority in reducing energy consumption and saving time.