The internal standard method is one of the main methods used in laser-induced breakdown spectroscopy (LIBS) for quantitative analysis. The key of the internal standard method for quantitative analysis is the internal reference selection. Fe 438.35 nm is selected as the analytical line. Area of 434~441 nm、Al 309.29 nm、Si 288.17 nm、 Ca 317.9 nm are selected as internal standard parameters for quantitative analysis of Fe in cement samples. The correlation coefficients of calibration curves are 0.993、0.962、0.992 and 0.846，respectively. By analyzing the intensity ratio of each internal standard element and Fe 438.35 nm at different delay time, as well as the dispersion of multiple measurement data of each internal standard element, it is obtained that when LIBS is used for quantitative analysis with internal standard method, the internal standard element which has similar changes to the analytical spectral line in the vicinity of delay time should be choosen. This can effectively decrease the quantitative analysis error caused by laser jitter and improve the accuracy of quantitative analysis.