Reference hardness blocks are an essential and infallible part of a measuring traceability chain for the measuring quantity of hardness. Their quality directly influences the measurement uncertainty of hardness measurement. For that reason reference hardness blocks must cover the whole scale of hardness values. Reference Vickers hardness blocks for the high hardness range are produced up to hardness values of approximately 1500 - 1600 HV1. Development of reference Vickers hardness blocks by different powder metallurgy processes was started in order to ensure measurement traceability for the hardness values of approximately 2000 HV1, as well as to enlarge the spectrum of materials and processes of manufacture. The application of tungsten carbide nano powders as a starting material, used for the first time for the block manufacture, provided for better microstructural and metrological characteristics than with the existing reference Vickers hardness block from a foreign producer, which represent a standard reference material, thus confirming the hypothesis of a doctoral dissertation. Developed blocks, with regard to the achieved microstructural and metrological characteristics, could potentially represent reference material for hardness after confirming the stability of the hardness over a longer period of time. The theoretical part of the doctoral thesis consists of three main parts contained in the title of the dissertation; hardness measurement, reference hardness blocks and powder metallurgy. Hardness measurement includes the definition of hardness measurement with described traceability and brief review of the Vickers hardness method. Characteristics of the reference hardness blocks with special emphasis on the reference Vickers hardness blocks, material and calibration procedure are described in detail. The area of powder metallurgy, as an extremely broad and extensive area, is described partly focussing on the parts that are the subject of the dissertation. The experimental part of the doctoral dissertation is complex and consists of several parts. The primary objective of the doctoral thesis was the development of reference Vickers hardness blocks by the powder metallurgy process. Different processes of powder metallurgy - liquid phase sintering in hydrogen and sinter HIP - were used for the development of the blocks, with the latter consisting of a number of separate yet imminent technological operations, such as milling, drying, waxing, granulating, compacting and sintering. The parameters of technological process of obtaining were varied in order to determine the optimal for each of the applied process and to achieve material with best characteristics. After the development and manufacturing, detailed analysis of reference Vickers hardness blocks was carried out. Obtained features starting with microstructure to final requirements placed on the metrological characteristics of the blocks were analysed, with special emphasis on the uniformity of the test surface as the most important property. In order to ensure the reliability of hardness measurements the inter-comparison on the primary micro hardness standard according to HRN EN ISO 6507-3 was carried out on the basis of which the measurement uncertainty of developed reference Vickers hardness block calibration was calculated. Finally, an analysis of the overall test results and conclusions on each of the applied process of powder metallurgy for the development of reference Vickers hardness blocks were made.