Biological diversity - means the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ekological complexes of which they are part; this includes diversity within species, between species and ecosystems, as Biological Diversity Convention says. In this work was made analysis of forest data of State Forest Enterprise of Kaisiadorys, Buda forest district. Atention was paid to the forest elements that can promote biological diversity. The archive data of managment (1977,1987,1996,2003 years)of Buda forest district used for assessment. Stand species diversity was analyzed using Number of species, Diversity, Proportionality and Dominance indexes. Thestand diversity dynamics of the Buda forest district was analyzed accordind to these indexes. There also were analyzed Species of Data Red Book of Lithuania of forest district, reserves teritories and key habitat teritories of Buda forest district.That supported to mark 2 teritories of Great biodiversity and 8 hotspots of biological diversity on the map of analyzed forest district.