During a ten-year period collaborators of the Research Laboratory of the National Institute for Cultural Property have been conserving a number of wooden articles removed from sea or lake water, or under the permanent level of subterranean waters. According to the absolute wood humidity (dry - humidity below 22per thousand; semi-dry - from 22 up to 32per thousand; wet - from 32 to 80per thousand, and very wet - above 80per thousand), the conservation method is selected respectively. For example in the case with Rudan , found in the Black Sea, and the one-log boat, whose humidity was less than 22per thousand, methods, under which dry wood is conserved, were applied. The wooden coffin excavated near Bourgas, with a humidity 24, 6per thousand and the knife with wooden holder and holster from the coffin in the town of Pliska with humidity from 25 to 32per thousand have been conserved with PEG dissoved in water and ethylalcohol, the water being continuously replaced by alcohol. Parts of water-collecting equiment in the town of Pernick with humididty 50 to 62per thousand were soaked in water until it become more than 80per thousand. These parts were conserved in a bath with water solution of PEG by increasing the concentration from 7 to 90per thousand. A one-log boat found in the Varna lake with humidity from 135 to 142per thousand was also conserved in a bath as stated above. The results from conserving the above-mentioned articles are very good.