The investigation during 1990-1993 on natural enemies of coffee stem borer Xylotrechus quadripes CHEVROLAT indicated that there were at least three hymenopterous parasitoid species belonging to Pristaulacus sp. (Aulacidae), Diastephanus sp. (Stephanidae) and a species of Mesostenini (Ichneumonidae) in northern Thailand. Among them, Pristaulacus sp. showed the highest parasitism with 18.1-35.0% and seemed to be the most important species for biological control of X. quadripes population. The longevity of male and female adults of the parasitoid were 3-6 and 6-10 days respectively.