Jatropha curcas(L.) is an important oil crop to refine biodiesel from its seeds, and biodiesel will develop to an industry on a certain scale in China. In order to get a raise in its fruit set ratio, improve its yield, and provide scientific basis for largescale planting, we investigated foraging insects and main pollintaing insects in the halfcultivated J. curcas population in Yuanjiang County, Yunnan Province in 2006． It was planted along a country road as a hedge on a flatland in Yuanjiang dryhot valley. Near it were some economical crops including Mangifera indica L., Musa acuminata Colla, Jasminum sambac (L.) Ait., Saccharum sinense Roxb which provided good habitat for insects. The plant produced flowers in racemose inflorescences, with dichasial cyme pattern. The flowers of J. curcas were unisexual, and male and female flowers were produced in the same inflorescence which showed needing mates to help its pollination. Normally, the inflorescences produce 184±189.02（88～238）male flowers with bright yellow stamens.  9.94±29.58（0.21～21.57）of them open every day on the crown of the tree which make a great floral display. And both male and female flower produced flower odor and nectar. Its salvershaped flower base promised many kinds of insect harvesting honey. There were amounted to 35 foraging insect species, belongingto 5 orders and 20 families. Half of them belong to Hymenoptera, while other belongs to Diptera, Lepidoptera, Hemiptera, and Coleoptera. By comparing the number and the pollination effectiviness (including their foraging behavior, foraging frequency, and daily activity rhythm)of the foragers, we determined the main pollination insects: Chrysomya (Compsomyia) megacephala Fabricius, Apis cerana Fabricius, and Catopsilia pomona f. Crocale. In addition, these species had different foraging behavior. The former two were smaller in body size than the honeybee, making them easy to transfer pollen from the stamens to the stigmas. But the honeybee was more numerous, compensated for its pollencarrying ineffectiviness. The daily activity rhythm was different among three pollinators , and it showed identical between the male and female butterflies. Furthermore, the composition of foraging insects was influenced by the weather conditions, the floral display, and habitat conditions. Finally, we discussed the relationship between J. curcas and its foraging insects and concluded that the main pollinators were different with changed time and space.