Abstract:The bostrychid powder post beetle,Heterobostrychus aequalis Waterhouse is a serious borer of rubber wood.It has 2~3 generations a year and attacks about 16 species of hardwood in Hainan Island.A control test with a new water soluble preservative TWP was carried out and the results were as follows: (1) retention of TWP preservative in wood at 1.0 kg/m3 can eradicate its egg-larvae up to 100%;(2) green sawn timber of rubber wood can be treated with 2% TWP by vacuwm pressure or oscillating pressure methods and an enduring protection effect will be obtained with a retention dose of TWP in wood no less than 3.7 kg/m3;(3) the TWP preservative is safe to human being,animals and environment for there is no chlorophenol compounds included.