[en] New data of the U-Pb dating of zircons of magmatic and metamorphic complexes of the Baikal-Patomskoe Upland are presented. More than 40 uranium-lead data were analyzed. The results obtained permit to conclude that the region has a polycyclic development. Main geochronological stages of the magmatic and metamorphic events were established. Lower Proterovic substrate age is found to be 2114+-22 millions of years. Late Kerelian (Akithan) stage (1800-1860 millions of years) are revealed as well as Early Paleo oic (556-420 millions of years) and Hercynian (340-270 millions of years). Violations in the zircon radiological systems are in the range of 473+-23 million of years. Geochronological gap (^window⁾ was found to bt in the limits of 1800-1300 millions of years