Investigations on the effects of Hylotrupes bajulus (L.) and Trichoferus griseus (F.) (Coleoptera: Cerambycidae) damaged on wooden constructions on some mechanical and physical characteristics of wood This study was carried out in natural and laboratory conditions in Mugla province between 2003–2005 years. Both harmed and unharmed samples (by insects) of Pinus nigra, P. brutia, Abies spp, Juglans regia, Fagus orientalis and Populus species which are used most commonly in wooden constructions were taken from log warehouses of public institution of Ministry of Forestry, and of private organizations to the laboratory environment. Samples which are both control and destroyed by insects were categorized according to wood species by means of random selection technique. Wood destroying species collected in the surveys have been identified by experts as Hylotrupes bajulus (L.) and Trichoferus griseus (F.) (Coleoptera: Cerambycidae). According to the findings obtained, the highest pressure resistance and tensile resistance value was found for Fagus orientalis and the lowest was found for Populus sp. for both infected and control samples. The highest static bending pressure value was found at control