In the present study,by measuring the A3 005 (representing unsaturation),A985 (representing conjugated fatty acids),A960+A985 (representing trans-fatty acid ) of southern common vegetable oils (peanut oil,corn oil,canola oil,soybean oil,sunflower oil,tea seed oil and olive oil),“waste oil” and overdue vegetable oils,the pass-setting-range of these three index values for the vegetable oils was obtained.On this basis,a method for rapid screening unqualified vegetable oil (expired,adding low-cost oil,adding “waste oil”) was established.The method effectively improved the monitoring efficiency of vegetable oil.With this method of screening a number of suspected substandard oils were proved unqualified by determination of fatty acid composition and 11,12,13,17 fatty acid content.Through the combination of several detection methods,the causes for disqualification of vegetable oils can be further inferred.