The isomerization and redistribution reactions of 2,5-dichlorotoluene (2,5-DCT) over Lewis acidic AlCl3 catalyst were investigated at the reaction temperatures ranging from 392.15 K to 452.15 K. 2,6- (3,5-, 2,4-, 3,4-, and 2,3-) Dichlorotoluenes (DCT) with the yields of ca. 5.6%, 9.6%, 16.2%, 3.3%, and 2.3% were formed via the isomerization reactions at equilibrium. Chlorobenzene (CB), dichlorobenzene (DCB), and dichloroxylene (DCX) with the yields of ca. 0.5%, 19.2%, and 20.4% were formed via the redistribution reactions. Valuable chlorinated aromatics, DCT, DCB, and CB, with a high total yield of ca. 57% were formed via the catalytic isomerization and redistribution of 2,5-DCT. The isomerization thermodynamics analysis revealed that the isomerization reactions were endothermic and the yields of isomers were slightly affected by the reaction temperature.