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Due to the intrinsic nature of a heterogeneous and anisotropic microstructure of cement based materials and the small indentation size, the measured microhardness values are subject to considerable variability.This work presents an in-depth assessment of microhardness of a hardened cement pastes (HCPs) from a statistical perspective.Hundreds of microhardness measurements were conducted on a HCP sample using a Vickers Microhardness Tester.The results shown that the microhardness measured from the HCP feature significant scatter and a large standard deviation, varying from tens to hundreds.The data-set of microhardness values was not normally distributed but fit best with a three-parameter lognormal model.Using a statistical software, the probability density function of the microhardness distribution can be readily obtained.The arithmetic mean and its 95% confidence intervals of the measured microhardness values can be used to best represent the microhardness characteristics of HCPs.