The present invention relates to a method for correcting measuring errors of a long-distance scanning laser radar, comprising: S1, establishing a measuring model and acquiring a positional relationship between a measured point and a coordinate origin; S2, acquiring an actual positional relationship between the measured point and a laser radar and establishing error models of three major error sources; S3, performing a sub-parameter measuring experiment on the laser radar to acquire major sample data of the three major error sources; S4, analyzing probability density distribution of the three major error sources with a statistical method to obtain error correction samples of the three major error sources in a three-dimensional coordinate system; S5, acquiring three-dimensional coordinate samples according to the error correction samples of the three major error sources and the measuring model; and S6, correcting a three-dimensional coordinate measuring point in real time.