Wood spruce has excellent properties such as toughness, elasticity, weathering resistance and chemical resistance. Its use is predominantly where the higher durability requirements are imposed. In Slovakia, the use of larch wood less widespread, caused partly by legislation STN EN 1912. In order to wood Slovak larch added to the STN EN 1912 is necessary to show the characteristic values (strength, flexibility and density).The master thesis has experimentally tested spruce wood grown in Slovakia. On the test body of design dimensions (50 x 150 x 3000 mm, n = 51) have a bending test of a norm SNT EN 408 detected flexural module (local, global, global to the shear bar 650 and the global measured in shear) and the shear modulus. Additional bending strength and wood density were also evaluated. The results were evaluated by new mathematical and statistical methods according to STN EN 14358 and implemented into the characteristic values defined in STN EN 384. The results were applied in the model of spruce strength classes - experimental and standard parameter level. The strength classes for planks in the test set showed higher characteristic flexural strength values. The line of classes according to STN EN 338 underestimates tested spruce wood in all classes of strength. For the same elastic modulus Em,0,mean spruce wood has considerably higher flexural strengths in strength classes C30, C24 and C16.