Rate constants of methanolyses of para-Z-substituted benzenesulfonyl chlorides have been determined in various isodielectric solvent mixtures. A third-order kinetic behavior has been observed in the methanolysis of p-nitrobenzenesulfonyl chloride in methanol-nitromethane mixture from the correlation figure of logarithms of rate constants were plotted against Y-values based on solvolyses of 1-adamantyl tosylate. $S_N1$-$S_N2$ mixing mechanisms are favored by neutral or weak electron-donating and weak electron-withdrawing substituents of p-Z-substituted benzenesulfonyl chlorides in methanol-nitrobenzene mixture. While the methanolyses of para-Z-substituted benzenesulfonyl chlorides in methanol-ethylene glycol solvent mixture are appropriate for $S_N2$ mechanism from the mechanistic criterion by means of m-values.