Abstract: Lightning electromagnetic pulse (LEMP) can be affected by radio frequency interference and radiowave propagation.Thus the distortion of the waveform is generated, which can affect the recognition of the lightning property and the quantitative estimation of the position and strength.In this paper,the correlation coefficient of a large number of measured LEMP waves is studied and analyzed, and the rules of using the waveform correlation coefficient to eliminate the gross error of LEMP are summarized.At the same time, the influence of propagation path on waveform correlation is also analyzed.Finally, a method of eliminating the gross error of LEMP is proposed by comprehensively utilizing time correlation and waveform correlation.