In order to study such nanomechanical properties of the zirconium hydride as nanohardness, nanoindentation tests have been carried out in the present study. As reference data, macroscopic mechanical properties of the zirconium hydride such as Vickers hardness have also been measured. The zirconium hydride specimens were fabricated directly from pure zirconium metal in a modified UHV Sieverts apparatus, and had the hydrogen contents with 1.5-1.7 H/Zr. The nanohardness of the zirconium hydride increased with decreasing maximum indentation load, which has been referred to as indentation size effect (ISE). The zirconium hydride had higher nanohardness than crystal-bar zirconium and pure zirconium, which was qualitatively in good agreement with the results of the Vickers hardness tests. The work hardening surface layer due to polishing the samples strongly affected the nanohardness, but barely affected the Vickers hardness. It was considered that the difference between the values of the nanohardness and the Vickers hardness were caused by not only the ISE, but also the difference of the indenter geometry and the testing method between the nanoindentation and the Vickers hardness test.