The age and geochemical characteristics of alkaline rocks of the Dugda massif (Eastern Tuva), attributed to the East Sayan Late Paleozoic rare-metal magmatic zone, have been determined. The massif is composed of nepheline syenites, which dominate over alkaline quartz syenites and alkaline granites. The age of the rocks has been estimated by the 40 Ar/ 39 Ar method for amphibole and the U–Pb SIMS method for zircon. The age of the rocks was 291 ± 5 Ma for nepheline syenites, 284 ± 2 Ma for alkaline quartz syenites, and 285 ± 4 Ma and 287 ± 1 Ma for alkaline granites. These estimations make it possible to determine the age of the massif with an average value of ~287 Ma. Rocks with different compositions are characterized by close geochemical characteristics. They are enriched in the majority of incompatible elements in comparison with the average composition of the Earth’s crust and are characterized by multi-element spectra similar to A-type granitoids. Variations in the contents of the incompatible elements in the rocks of the massif exceed two orders of magnitude and reach ore concentrations (Zr up to 2.5 wt %, Nb up to 0.2 wt %, Ta up to 250 ppm, and Y up to 0.2 wt %). The geological position of the massif and specific features of the composition of its rocks, allowed us, firstly, to clarify the relationship between the East Sayan Late Paleozoic rare-metal zone and the fault system, which defines the western boundary of the Tuva–Mongolian microcontinent; secondly, to limit the time of alkaline magmatism to the interval of 309–285 Ma; and thirdly, to conclude that the spectrum of rare-metal igneous rocks of the zone is not limited to alkaline granitoids, but also includes alkaline nepheline syenites.