Medicine intermediates terephthalic acid synthesis method, comprises the following steps : 2 mol 4-ethyl-5-amino-benzyl alcohol and 4-5 mol 2, 5-dimethy1-2, 5-hexanediol were added to the reaction vessel, raised the temperature of the solution to 60-67 V, controlled the stirring speed at 170-190 rpm, kept for 130-170 min, then add 3-4 mol dicyldiphenyl titanium in 6 to 9 times, raised the temperature of the solution to 80-86癈, kept for 70-90 min, precipitated solid, filtered, the solid washed with potassium bromide solution, washed with dipentyl ether solution, 4-heptanone solution, reduced solution temperature to 3-6癈 , recrystallized in diisopropyl ether solution, dehydrated with dehydration, got the finished product terephthalic acid.