A preconcentration method using Amberlite XAD-16 column for the enrichment of aluminum was proposed. The optimization process was carried out using fractional factorial design. The factors involved were: pH!, resin amount, reagent/metal mole ratio, elution volume and sampling flow rate. The absorbance was used as analytical response. Using the optimised experimental conditions, the proposed procedure allowed determination of aluminum with a detection limit (3 sigma/s) of 6.1 mu g L(-1) and a quantification limit (10 sigma/s) of 20.2 mu g L(-1), and a precision which was calculated as relative standard deviation (RSD) of 2.4% for aluminum concentration of 30 pg L(-1). The preconcentration factor of 100 was obtained. These results demonstrated that this procedure could be applied for separation and preconcentration of aluminum in the presence of several matrix.