The establishing method of dynamic model of liquid phase catalytic paraxylene oxidizing reaction comprises utilizing the reaction temperature x1 and mixed material composition including solvent ratiox2, Co catalyst concentration x3, Mr catalyst concentration x4, and Br promoter concentration x5 and the rate constant nerve net model to find out the rate constants ki, where i=1,2,3 and 4, of the steps in reaction network of industrial liquid phase catalytic paraxylene oxidizing reaction, and to find out the contents of PX, TALD, PT acid, 4-CBA, TA and other intermediate products and estimate products. The rate constant model can describe the effects of different factors on the reaction in the industrial reactor.