The present study investigates the kinetics of lead and copper removal from oil-field brine by potential sorption. A population balance equation, coupled with a mass balance equation, was used in the estimation of kinetic parameters. Metal removal was performed by potential sorption of lead and copper through CaCO3 precipitates induced by the reaction of Na2CO3 and CaCl2. The oil-field brine was selected from an oil well in Gachsaran, Iran. The crystal size distribution of the solid phase was measured by dynamic laser scattering analyzer, and the liquor phase was analyzed using atomic adsorption. The morphology of calcium carbonate particles was illustrated using scanning electron microscopy and X-ray diffraction. The results showed that the presence of copper and lead decreases the average size distribution of calcium carbonate particles by influencing the kinetic parameters. Lead and copper concentrations were reduced from 2.911 to 0.127 ppm (95.63% removal) and 0.476 to 0.025 ppm (94.74% removal), respectively, in exchange for 12 g CaCO3 consumption per 100 ml oil-field brine.