Statistical distribution of grid indentation data measured in multiphase materials can be significantly affected by the presence of an interface between adjacent materials. The influence of an interface on the distribution of measured indentation moduli was therefore characterized in model metal–metal, ceramic–ceramic, and metal-ceramic composites. The change of properties near the interface was simulated by finite element method and experimentally verified by indentation in proximity of the boundary between two phases with distinctly different mechanical properties varying the depth of penetration and the distance from the interface. Subsequently, the conditional probability of measuring near the interface was quantified by beta distribution function with parameters dependent on the size of the volume/area affected by the presence of the interface. Using this approach, the intrinsic properties of the individual materials were successfully extracted from the experimental grid indentation data.