Abstract: Studies on the Essential Oil Components of Tooma Sinensis Leaf(Ⅰ)Extraction of its Oil and Selection of Gc/MS ConditionsGu Yueling;Hu Gengyuan(Department of Chemistry,Zhejiang University,Hangzhou 310013,China)Fu Shuiyu(Department of Chemistry,Hangzhou Teachers College, 310014,Hangzhou, China)Received 1994-07-20Abstract:The article introduces a new pretreatment method-simultaneous distillationextraction(SDE). The essential oil of Tooma Sinensis leaf are extracted by SDE and 71components of the essential oil are determined by GC/MS.Keywords:simultaneous distillation-extraction,essential oil of Tooma Sinensis leaf,GC/MS.