The paper summarizes the results of radioecological monitoring in the mountainous regions of Armenia in order to identify the distribution of radionuclides (natural Ra-226, Th-232 and artificial Cs-137) and the associated environmental risks in the mountainous environment of Armenia. Soil samples from the surface of eight mountain ridges and massifs were collected along altitude (900–3200 m above sea level). Gamma spectrometry has been used to identify radionuclides and measure activity concentration. A significant correlation was found between Ra-226 and Th-232, no statistically significant correlation was observed between Cs-137 and natural radionuclides. The results of the Kruskal-Wallis test reveal the height-dependent pattern of the studied radionuclides in the soil: the concentration of Cs-137 activity increases with height, the variances of the average values of the Ra-226 and Th-232 activity concentrations do not change in absolute height. An assessment of the ecological risk to non-human biota using the ERICA Tool identified risk factors (RQs) and limiting reference organisms in the mountain environment is presented.