The invention relates to an infrared spectrum-based crude oil type identification method, which comprises: determining the mid-infrared spectrums and the near-infrared spectrums of various types of crude oil samples, carrying out second-order differential treatment, taking the polar coordinate projection scores of the absorbance of each crude oil sample at five spectrum areas such as W1 of 1650-1800 cm<-1>, W2 of 4000-4500 cm<-1>, W3 of 4500-5000 cm<-1>, W4 of 5000-5500 cm<-1> and W5 of 5500-6000 cm<-1> on the X-axis and Y-axis, establishing a crude oil spectrum identification database throughthe polar coordinate projection scores, determining the polar coordinate projection scores of the absorbance of crude oil to be identified at the five spectrum areas on the X-axis and Y-axis, calculating the distances between the identification vector of the crude oil to be identified and each crude oil sample vector, and comparing the minimum distance to a set threshold, wherein the corresponding crude oil and the crude oil to be identified are the same type of the crude oil if the minimum distance is less than the threshold, and if the minimum distance is not less than the set threshold, the same crude oil as the crude oil to be identified does not exist in the crude oil spectrum database. With the method of the present invention, the crude oil sample identification speed and the crudeoil sample identification accuracy can be effectively improved.