Strong-acid cation exchange resins were employed to catalyze to synthesize 1,3,5-trimethyl-2,4,6-tris(3,5-di-tertbutyl-4-hydroxybenzyl)benzene(antioxidant-1330). During the reaction, a methanol-containing binary azeotrope mixture which was generated as by-product need to be distillated. The effect of type and quantity of resins, reaction time, repeated times of catalyst on the yield were investigated. Results of experiments show that the activity of big bore resins without water was higher than aquiferous ones. The most preferred conditions are as follow: n(3,5-di-tertbutyl-4-hydroxybenzyl methyl ether):n(mesitylene)=3.6:1, m(resin):m(3,5-di-tertbutyl-4-hydroxybenzyl methyl ether)=1.03:1, reaction temperature 40℃ and reaction time 2 h. The yield of UV-1330 is 85.7% which can be kept above 82% after repeat used 6 times. In this new process, there is no waste acid and the effluent can be reduced 50 to 60 percent compared with prior process.