In the present paper there is described a kinetic electrodialysis method using ionexchange membrane under controlled conditions for the determination of the mode of occurrence of uranium in ores. With the employment of buffer and a large excess of ions, the pH and ion concentrations of the electrodialysing solution can be controlled, so that the complex kinetic equation for the ionic migration can be simplified, and the rate of the electrodialysis of uranium in ores, K, can be quantitatively determined for characterizing its mode of occurrence. Practical applications are given.