In view of some technical problems that exist in the measurement of time-extracted quantity curves of the electric extraction method, this paper, based on theoretical and experi-mental research, has worked out formulae of concentration correction and methods of correction for time-extracted quantity curves of sampling with supplementary liquid and without supple mentary liquid, and made clear that the contents of electric extracted ions are related to electric quantity Q = I·t, i. e., determined by the product of intensity of electric current (I) and time of power supply(t). It has been confirmed that, when the style of discontinued power supply is adopted, the extraction results are basically consistent with variation characteristics of time-extracted quantity curves so long as the cumulative electric quantity is equal to the quantity of continuous power supply.