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The effect and mechanism of the removal of Pb2+ from an aqueous solution by using brucite as the adsorbent were studied.It was revealed that the increase in pH of brucite suspension, as a result of the release of magnesium hydroxide into the suspension,leads to a sharp rise of the adsorption amount of Pb2+ on brucite. The synergism of buffering and adsorption capacities of brucite is responsible for the removal of Pb2+ from the aqueous solution. The coexistence of Cu2+ with Pb2+ causes a decrease of their adsorption on brucite due to a competition for surface sites and brucite exhibits a higher adsorption capacity for Pb2+ than for Cu2+. The percentage adsorption of Pb2+ on brucite could reach 96.38%, 97.20% and 94.09% respectively with the initial pH of the suspension pHi = 1.76 (initial Pb2+ concentration [Pb2+]I = 20 μmol/L), 1.82 ([Pb2+]I = 100 μmol/L) and 1.84 ([Pb2+]I = 500 μmol/L). It was concluded that brucite is a very efficient mineral adsorbent for Pb2+ removal from polluted acidic water.