The results of the study of the mires of the Lembolovskaya Upland (Central Upland of the Karelian Isthmus) conducted by a team of authors in 2017–2019 are presented. The materials are supplemented by data obtained in 1989 during the work of the Northwestern expedition of the Komarov Botanical Institute of the Russian Academy of Sciences (BIN RAS), in the work of which V.A. Smagin took part. The mires of the Lem-bolovskaya Upland, which are not typologically different from the mires of the rest of the Karelian Isthmus, have a number of features due to the relief, postglacial history, and climate. On the upand, there are presented sloping, terraced bog massifs and systems, with a number of rarely occurring types of mire sites. On the upland bogs, plant species and plant communities of bogs of the Baltic Sea are common. In addition to the bogs, there occur transitional mires and fens placed only in deep river and lake valleys, where they receive limno-genic, alluvial, and pressure ground water-mineral nutrition.