Abstract: Under the presupposition of plug flow with dispersion, the partial differential equation (s.eq.3) for two-dimension (radial and axial) dispersion in a pulsed extraction column is deduced. Under the condition of pulse input of tracer at the center of the column, the mathematical solution for eq.3 is found and given in this paper, that is,the mathematical model for two-dimension dispersion (s.eq.4). This mathematical model corresponds to the measured experimental data (s. Fig.3). With the Marquardt method for minimization of sum of square of errors between model and experimental data, the radial dispersion coefficient and axial dispersion coefficient could be determined at the same time.