Boehmite and alumina nanostructures were prepared using a simple green sol–gel process in the presence of alanine in water medium at room temperature. The uncalcined (dried at 200°C) and the calcined materials (at 500, 600 and 700°C for 4h) were characterized using XRD, TEM, SEM, N 2 physisorption and TGA. Nanorod aluminas with a possible hexagonal symmetry, high surface area and relatively narrow pore size distribution were obtained. The surface area was enhanced and crystallization was retarded as the alanine content increased. The morphologies of the nanoparticles and nanorods were revealed by a transmission electron microscope (TEM).