The thesis describes the wood liquefaction optimization of different wood species using different reagents and various acid catalysts. Wood was liquefied for 2-4 hours, at temperatures between 150-180 °C. Every 15-30 minutes a sample was taken, then filtrated, and its residue ratio calculated. Hydroxyl numbers were determined for the samples of liquefied beech wood. The results show that wood species does not effect wood liquefaction; there are no differences in liquefaction of hardwoods and softwoods. Neopentyl glycol and trimethylol propane were the most effective among reagents, while sulphuricand p-toluenesulphonic acids among acid catalysts. A rate between amount of wood and reagent was also investigated; the results show that the rate has no effect on wood liquefaction.