CNT composites have extremely high elastic modulus and tensile strength as high as 1 TPa and 200 GPa, respectively and hence CNTs are used as strong, light, and tough fibers for nanocomposite structures. The effective utilization of nanotubes in composite applications depends strongly on the ability to disperse CNTs homogeneously throughout the matrix with good interfacial bonding to achieve load transfer across the CNT-matrix interface. A colloidal processing route is an effective way to improve the mechanical properties of carbon nanotube-alumina composites. By colloidal processing multi components could be distributed evenly when they possess similar surface properties by adjusting the surface properties of for example alumina powder and that of CNTs, it is feasible to make them bind together with attractive electrostatic forces, which produces strong cohesion between two phases after sintering.