The influence factors of solvent,raw material granularity,extraction time on simultaneous distillation extraction method were studied by single factor experiment.The results showed that there was the best as extraction solvent,because the chromatographic peak showed more information and is relatively less toxic,the extraction rate was 8.2%;when Zanthoxylum particle size was 40 mesh,the extraction rate reached to 9.4%.The best extracting time was 3 h,Zanthoxylum essential oil extraction rate was 9.5%,when use ultrasonic for 5min as the assistant treatment,Zanthoxylum essential oil extraction rate could reach to 12%,and chromatographic peak showed more information.The experiment provided a good foundation in further research on zanthoxylum.