Abstract: Spent sulfite liquor, after alcoholic fermentation and dislillation was used in long-middle period tapping of pine trees (Pinus Massoniana). An average 32.8% increasing in oleoresin yield was obtained in small scale experiment lasting three years. In productive scale experiments, oleoresin yield was increased roughly 30%. The yield was somewhat varied owing to the differences of geographical distribution, standing circumstances, arboreal growth, and tapping technic. The labor productivity of tapping was raised by about 27%, while using a tube applying ax of gas pressure type. The tapping technic with spent liquor was fundamentally similar to that of ordinary method, excepting additional applying procedure. Concentration of waste liquor used was changed with the weather. The specific gravity 1.05, was generally used and 1.03 was used in dry season. The dose for a pair of streaks averaged 0.5-1.0g. Spent liquor tapping showed more efficient to those trees with lower resin productivity. It could also give greater gain in drier, lower temperature and shorter sun-shine tapping seasn. As it prolongs the length of tapping season, total output of oleoresin in one year can be increased. Spent liquor was harmless to man, cattle, and clothes. Tapping with spent liquor would not bring bad effects to growth of trees in comparison with ordinary tapping method. After washing with water, oleoresin produced with spent salfite liquor could be processed to give rosin and turpentine of good quality. The products could satisfy the specifications for rosin and turpentine published by the Ministry of Forestry.