Abstract: Chemical reaction takes place when two chemical liquids flow parallelly and diffuse into each other.A solution for chemical reaction kinetics under the convective coordinate was presented to solve convection-diffusion chemical reaction equations. Under this coordinate, these equations became reaction-diffusion equations without convection terms, viz. only reaction and diffusion terms was calculated in each time step. The flux of the liquids was shown in the increase of calculation region as time step increased;and the time to react and diffuse of each particle was equal to the time after they flow into the calculation region, so the time to react and diffuse for every particle in the liquids differed from each other. This method avoided the spurious numerical oscillations in calculation caused by the flow discontinuity in front of the materials, which showed serious unstable influence on solution.Numerical examples demonstrated that this algorithm was effective.