Hydrolytic rate constants of p-substituted phenol esters of carboxylic acids with various chain lengths were measured in 1:1 (v/v) Me_2SO-H_2O. Amylose accelerates the hydrolytic rates of all substrates, but the catalytic patterns are different for long and short chain substrates, i. e., acetates (2-X) show 2nd order kinetics, dodecanoates, (12-X) and hexadecanoates (16-X) follow Michaelis- Menten saturation kinetics. The dissociation constants K_d of inclusion complexes are dependent on the chain length of substrates. The rate constants k_(un), k_(obs), k_2 and k_c of 12-X and 2-X conform to the Hammett relation, the ρ values are almost the same, whether in the presence or absence of amylose. But k_(un), k_(obs) and k_c values of 16-X all cannot be correlated by the Hammett equation because of the aggregation and self-coiling of 16-X in this poor solvent. Thermodynamic parameters ΔH_i and ΔS_i of the inclusion process and activation parameters ΔH_c~≠ and ΔS_c~≠ were obtained from the temperature dependence of K_d and k_c. The results indicate that the formation of inclusion com- plexes between amylose and substrates is an entropy disfavored and enthalpy favored process. Com- parison of ΔH_c~≠, ΔS_c~≠ with ΔH_(un)~≠ and ΔS_(un)~≠ shows that the acceleration of hydrolysis of long chain substrates by amylose is caused by the formation of helical inclusion complexes. Hydrolytic rate constants of p-substituted phenol esters of carboxylic acids with various chain lengths were measured in 1: 1 (v / v) Me_2SO-H_2O. Amylose accelerates the hydrolytic rates of all substrates, but the catalytic patterns are different for long and short chain substrates, ie, acetates (2-X) show 2nd order kinetics, dodecanoates, (12-X) and hexadecanoates (16-X) follow Michaelis- Menten saturation kinetics. The dissociation constants K_d of inclusion complexes are dependent on the chain length of substrates. The rate constants k_ (un), k_ (obs), k_2 and k_c of 12-X and 2-X conform to the Hammett relation, the ρ values ​​are almost the same, whether in the presence or absence of amylose. But k_ (un), k_ (obs) and k_c values ​​of 16-X all can not be correlated by the Hammett equation because of the aggregation and self-coiling of 16-X in this poor solvent. Thermodynamic parameters ΔH_i and ΔS_i of the inclusion process and activation parameters ΔH_c ~ ≠ and ΔS_c ~ ≠ were obtained from the temperature dependence of K_d and k_c. The results of that formation of inclusion com- plexes between amylose and substrates are an entropy disfavored and enthalpy favored processes. Com- parison of ΔH_c ~ ≠, ΔS_c ~ ≠ with ΔH_ (un) ~ ≠ and ΔS_ (un) ~ ≠ shows that the acceleration of hydrolysis of long chain substrates by amylose is caused by the formation of helical inclusion complexes.