none Natural parasitism of S. derogata and C. flava, 2 foliage-feeding lepidopterous pests of cotton, was studied for the first time in Chad (Bebedjia) in 1986 and 1987. The percentage parasitism of larvae of S. derogata collected from the field averaged 18,5% in 1986, a year with a low infestation of larvae, and 14,1% in 1987, a year with a high infestation. In 1986, Meteoridea testacea (Braconidae) was the most common parasitoid whereas in 1987, when more host larvae were available, Apanteles syleptae (Braconidae) was the most common species. In 1987, secondary parasitoids emerged from many of the braconid cocoons taken from the field to the laboratory for further study. In 1987, 15,7% of the larvae of C. flava collected from the field were parasitised. The primary parasitoids that emerged from these larvae were all specific to the species. The most common primary parasitoid was Aleiodes aligharensis (Braconidae). In contrast, the secondary parasitoids were not specific but were the same species that infested the coccons of the parasitoids of S. derogata.