The five articles of this publication deal with the biodiversity of northwestern Karelian Republic along the Finnish boundary and needs for its conservation. The studies cover geology and geomorphology of the area, mosaic forest and mire ecosystems as well as flora of vascular plants, lichens, bryophytes and hepatics, and also some plant communities were not described earlier: On the basis of the studies, proposed Kalevala national park as well as establishing some new small nature reserves were made. The results show that present nature reserves and conservation plans do not adequately guarantee the preservation of biodiversity in the region.