Fir and spruce wood specimens, 2×2 cm in cross section and 34 cm long, were pre-pared with true radial and tangential surfaces. All lateral surfaces of the wood specimens were drilled by laser beams to a depth of 0,4 cm (1/5 of specimen thickness) with two drilling patterns (distance between holes 1×1 cm and 1×2 cm) in order to improve the wood permea-bility of these refractory to impregnation species. After drilling and assessing the drilling ef-fect on mechanical properties of wood, wood specimens, 10 cm long, were impregnated with oil and CCB preservatives by using vacuum (0,6 mmHg) and pressure (1,5 bar) for 15 minutes and 30 minutes, respectively. The effects of the two laser drilling patterns on impreg-nability of fir and spruce wood specimens were measured and assessed. The results showed that both drilling patterns created by laser beams on all lateral surfaces of fir and spruce wood specimens at 0,4 mm depth improved the retention and penetration of preservatives in fir and spruce wood specimens. This effect was more pronounced in fir than in spruce. Between the two drilling patterns, the pattern with distances between holes 1×1 cm was more effective than that with distances 1×2 cm, in both species tested.