Alumina was synthesized via sol-gel technique by the hydrolysis of aluminium ion controlled by urea in aque- ous media. The resulting sol composed of Al(OH)3 particles coalesced and became a transparent gel. The freshly prepared gel was heated at 280°C to obtain alumina particles. The obtained particles were found to be amorphous � - alumina parti- cles with high porosity, characterized by FTIR, XRD and SBET techniques. Electron micrograph shows that the particles are nano-sized having non-spherical shape. Comparatively higher magnitude of adsorption of cationic surfactant indicated that the surface of alumina particles is negatively charged.