Drywood termites, Cryptotermes cynocephalus Light, were exposed to wood blocks and wood extractives of Neobalanocarpus heimii King and Shorea ovalis• KorthJ BL The results showed that the termites' survival and wood consumption were significantly higher on S. ovalis than on N. heimii. Termite survival and feeding response obtained on bioassays with sawdust, extracted sawdusts and extract treated filter paper, indicated that one factor affecting the variation in relative susceptibility of the woods to termite attack could be secondary compounds present in the wood.