ABSTRACT Complex mountainous relief and diverse geology that are common for the whole territory of Armenia are strong limiting factors for regional scale geochemical survey, for assessment of the geochemical background of naturally occurring radionuclides (226Ra, 232Th, 40K) and reference values of artificial 137Cs. Sampling transects spanned by altitude in mountain ridges and massifs, representing the main geological formations of the area, are informative enough for a pilot assessment of background and reference activity of radionuclides in soils. A total of 131 undisturbed soil samples were collected from 8 mountain ranges and massifs throughout Armenia. HPGe detector-based gamma spectrometry was used for the quantification of radionuclide activity concentrations. Geology and soil type were the main factors in the formation of radionuclide composition in the soil. The reasonably close estimates of naturally occurring radionuclide background activity were obtained from the application of ‘Median ± 2MAD’ and Tukey’s boxplot methods. The results yielded by both methods could be employed as a background, contingent upon the specific objectives being addressed. The distribution of 137Cs exhibits strong dependence on the altitude and therefore, its reference activity concentrations were estimated at distinct elevation intervals applying the ‘Median ± 2MAD’ method.