Surface-enhanced laser-induced breakdown spectroscopy (SENLIBS), with the advantage of higher detection sensitivity, is widely applied in the field of water quality monitoring. However, the self-absorption effect occurs, which reduces the accuracy of quantitative analysis. To correct for the self-absorption effect, the self-absorption coefficient (SA) iteration method was proposed. This method iteratively calculates the SA through the exponential fitting parameter of standard samples to correct the spectral intensity of standard samples and unknown sample. With this method, the SA values of Cr spectral lines were corrected to be closer to 1. As a result, the average limit of detection (LOD), average of the average relative error (ARE), and average root mean square error of cross-validation (RMSECV) were reduced from 0.118 ppm to 0.057 ppm, 39.94% to 14.00%, and 0.752 ppm to 0.403 ppm, respectively. This demonstrated that SA iteration method could improve the quantitative analysis performance of LIBS by correcting for the self-absorption effect.