The invention discloses a partial least square method-based pipeline corrosion prediction method under metro stray current. The method comprises the steps of 1, selecting a test point, and performing finite element simulation; 2, preprocessing data ; 3, obtaining a training sample; 4, selecting a first principal component pair; 5, carrying out regression of dependent variables and independent variables to principal components; 6, carrying out residual matrix replacement; 7, establishing a partial least square regression equation; 8, verifying cross validity; 9, removing redundant position variables, and selecting optimal sensor arrangement; and 10, testing the test sample. According to the method, the effective pipeline corrosion prediction current density is obtained through earth surface potential data obtained in the interval in combination with finite element simulation, the prediction regression equation is obtained according to the partial least square method, the corrosion condition of a pipeline is judged, the number of sensors is reduced, meanwhile, the prediction precision can be kept within the acceptable range, and the method has great practical significance for intuitively monitoring the corrosion condition of the pipeline and saving the cost.