The species composition of maize stemborers and prevalence of their natural enemies at five highveld (>1200 m) sites were studied by random sampling of borer life stages in maize fields. Busseola fusca Fuller (Lepidoptera: Noctuidae) was the dominant species and constituted 99% of all larvae and pupae sampled during the study. Cotesia sesamiae Cameron (Hymenoptera: Braconidae) was the most abundant and widely distributed parasitoid reared from B. fusca larvae, followed by Sturmiopsis parasitica (Curran) (Diptera: Tachinidae). Two hyperparasitoids, Aphanogmus fijiensis (Ferriere) (Hymenoptera: Ceraphronidae) (from C. sesamiae cocoons) and Dendrocerus rodhaini (Bequaert) (Hymenoptera: Megaspilidae) (from S. parasitica puparia) were recorded. Preliminary data on the occurrence of C. sesamiae and S. parasitica suggested that these two parasitoids complement each other by partially partitioning their niche and thus minimizing competition. However, firm conclusions concerning the host range and ecological adaptations of the two parasitoids cannot be drawn until detailed studies have been conducted countrywide, especially at lower altitudes (<900 m a.s.l.) where Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) and Sesamia calamistis Hampson (Lepidoptera: Noctuidae) predominate. none