The nature of the interaction between aluminum ions and leaves has been investigated. The effects of several factors including the concentratlon of leaves, the concentration of aluminum, and the presence of competing ions on the uptake of aluminum by leaves have been studied. Releasing aluminum from leaves by the effect of changing pH or the addition of foreign ions has been also studied. Results showed that increasing the leaf concentration increased removal of aluminum; the cations Zn2+, Ni2+, Pb2+, Cd2+, Mg2+, Fe2+, and Co2+competed with aluminum and reduced its uptake but Ca2+did not compete.