Abstract:In laboratory conditions the seed oil of angled bittersweet (Celastrus angulatus Maxim.), termed CA oil, possesses obvious antifeedant effect on Pieris rapae, Aulacophora femoralis, Henosepilachna vigintioctopunctata, Locastra muscosalis, Colaphellus bowringi and Calospilos suspecta.In the field experiments the efficiency of controlling Pieris rapae has been shown as follows: 86.5%, 91.16% and 85.37% obtained respectively by using 2%, 0.66% and 0.5% CA oil; 89.6% by using 10% Cypermethrin diluted 5000 times; and 79.81% by using the root-bark powder of angled bittersweet, which indicates that the controlling effect of CA oil is approximate to that of Cypermethrin and better than that of the root-bark powder.The field experiments have also proved that the CA oil exceeds DDVpboth in controlling effect and in yield increase when used against Aulacophora femoralis.Since the angled bittersweet has not only reliable pest-controlling substance in its seed oil, but also many other advantages, such a bundant resources, wide distribution, strong adaptability and high survival rate, it can be expeeted to be an important source of pest-controlling material and the CA oil to be a very promising natural plant insecticide or antifeedant agent.