Effects of suspension pH on stability and surface properties of alumina and silica nanosuspension were investigated. Nanosuspensions of alumina and silica used in the present study were produced by wet grinding in stirred media mill. The electrostatic stabilization of two types of nanosuspension was conducted by zeta potential and turbiscan analysis as a function of pH. The long-term stability analysis of alumina and silica nanosuspension was investigated using an optical analyzer. It was observed that particles gradually aggregated and settled with storage time and can be easily redispersed by mere shaking of suspensions under desirable pH conditions. Transmission electron microscopy images obtained at different suspension pH for both alumina and silica nanoparticles show that the state of aggregation is highly dependent on pH and found to affect particles morphology.