Study object – Spruce wood the time is ripe fact – finding in Trakai state forest enterprise, Trakai and Semeliskes forestry stalls. Study aim – Research spruce round wood data kind’s variation consistent pattern and make spruce steams sort models of structure. To reveal basic Lithuanian forest market’s development tendencies, determine main factors, characterizing dynamics of round wood kinds. Study methods – In tests on several groups of Norway spruce (Picea abies (L.) Karst.) comprising more than 309 trees in total, the method detected dynamics of round wood kinds have been evaluated of method correlation analysis with high accuracy. We validated the method both by measurements and by finite element modeling and simulations. Study results – It has been analyzed Norway spruce’s round wood structure models of Trakai state forest enterprise during 2003 – 2005 years. It has been estimated each round wood kind’s simulation with tabulation and evaluated kind of round wood for diameter fluctuation.