Abstract: In this paper,with reference to operating conditions of dihydrate Wet-process Phosphoric Acid(WPA)process used conventionally,the effects of the average rock particle size,sulfuric acid concentration and reaction temperature on the dissolution kinetics of Jinhe phosphate rock in a mixture of sulfuric and phosphoric acids were studied in detail experimentally,and consequently a series of dissolution kinetics curves were obtained.The Drozdov equation which takes into account the self-impeding effect is selected for simulating the dissolutin kinetics.With the aid of the Gioias modified mathematical model for the simulation of phosphate rock acidulation,an effective diffusion coefficient for coating on rock particles is calculated.