Between raw and heat treated specimens of beech (Fagus sylvatica L.) and three equal humidity balanced samples (with 33 %, 65 % and 87 % relative humidity) we performed comparative static tests, correlation test of evaluated elasticity modulus, bending hardness, deformation to fracture and evaluation of energy (force) needed for fracture. From creep experiment we defined elasticity deformation, restrained elasticity and plastic deformation of the component. Elasticity modulus, bending hardness, deformation to fracture and evaluation of energy (force) needed for fracture, are lower at heat treated samples at all three humidity levels. Heat treatment has smallest (minimal) effect of elasticity modulus, while it has greater effect on energy (force) needed for sample fracture. The heat treated specimens have very small restrained elasticity and plasticity components so they deform less, which leads to brittle fracture (crack). The higher humidity has smaller effect on heat treated wood, as it has effect on untreated wood, but in both cases deformation is increasing if humidity increases.