根据多元酸平衡体系中型体具有先出现先消失的特点，提出了用渐进因子分析与化学平衡结合迭代，从ｐＨ－分光矩阵中求解多元酸离解常数的新方法。用该法测定了多元酸茜素Ｓ和铬天青Ｓ的离解常数，并讨论了确定型体存在区域的经验式。结果表明该方法稳定、可靠、算法收敛快，所测得的离解常数与文献值吻合。 According to the fact that the mesomer in the polybasic acid equilibrium system first appears and disappears first, a new method for solving the dissociation constant of polybasic acid from the pH-spectroscopic matrix is ​​proposed by using the combination of the asymptotic factor analysis and the chemical equilibrium. The dissociation constants of polyacid alizarin S and chrome azure S were determined by this method, and the empirical formulas of the existing regions of the determinant were discussed. The results show that the method is stable and reliable, the algorithm converges fast, and the measured dissociation constants are consistent with the literature values.