To establish a nondestructive and rapid analysis method of determining iodine va lue in vegetable oil with no reagent using laser Raman spectroscopy combined with partial least squar e (PLS),taking soybean oil,olive oil,peanut oil,sesame oil and their blend oil as samples, their Raman spectra are collected,with the range of 250－2400cm－1,and th eir signals are assigned.A variety of experimental conditions affecting Raman spectroscopy determination are investigated. Take the iodine value determined by traditional Wechsler as contrast,with combin ation of chemometric methods to establish a Raman spectroscopy quantitative model of iod ine value.The experimental results show that the Raman spectroscopy peak shapes and displaceme nts of soybean oil, olive oil,peanut oil and cooking oil have a certain similarity,while the Raman spectroscopy of sesame oil has a strong fluorescence interference,and there is obvious differen ce of the peak intensity with the other vegetable oil samples.The iodine value correction mode l is e stablished with the coefficient of determination R²=97.49,and the cross-validation calibration standard deviation (RMSECV ) of 1.15.The test set standard error of prediction (RMSEP) is 1.57,and the coefficient of determination R^2is 96.47.The results show that the ap plication of Raman spectroscopy combined with chemometrics in the rapid detection of iodine value in vegetable oil is feasible.