The analysis of the water balance in Lake Munozero (2005) has shown that there is highpower receipt of underground waters in the lake. It is confirmed also by data on water mineralization in the Konchozero lakes system. According to the level of quantitative development of zooplankton with an average summer biomass about 1,0 g/m3 it is possible to refer L. Munozero to the category of oligo-mesotrophic lakes. The analysis of
bottom fauna specifies a good condition of food resources for benthophagous fish in the lake (biomass – 5,86 g/m², number – 5000 ind./m²). It is necessary to include the relict species – four-horned sculpin and the introduced species – Arctic char in the structure of the fish community of L. Munozero.