β-Al(OH) 3 microrods were synthesized by the precipitation of aluminate ions slowly added into a solution whose pH was kept constant by nitric acid. The purity, morphology, surface area and porosity of the product were characterized by XRD, SEM and N 2 adsorption, respectively. Rods, 1-10 μm long, with flat 0.5-μm wide bases, were obtained. The product was compared with bayerite obtained by the usual titration-like method (variable pH).