In the ICP-AES measurement system, the phenomenon of spectral superposition causes most of the spectral lines to be interfered by different degrees of overlap, which results in subsequent quantitative analysis errors. In this paper, the method of spectral overlap interference correction is explained and the evaluation function is established according to the mechanism of spectral superposition; By using the finite difference method to calculate the approximate second derivative and the distribution of the minimum value of the approximate second derivative, the minimum range of the characteristic wavelength of the neutron peak in the overlap spectral lines can be determined, and use the range as one of the initial conditions of the differential evolution algorithm. Then use the differential evolution algorithm to get the optimal solution of the evaluation function as the optimal eigenvector of the overlap spectral lines. The interference spectral lines and target spectral lines in the overlap spectral lines are analyzed by the optimal eigenvector. The effect of parameters NP and G on the performance of the differential evolution algorithm is tested by simulated overlap spectral lines data, and the feasibility of the spectral line overlap correction method proposed in this paper in the field of engineering is verified by measured overlap spectral lines data. The experimental results show that the differential evolution algorithm can be used to calculate the optimal eigenvector of the overlap spectral lines, and parse out the target spectral lines and the interference lines in the overlap spectral lines, thereby achieving the overlap spectral line interference correction, which lays the foundation for the subsequent quantitative analysis of element content.