AbstractNesidiocoris tenuis(Reuter) (Heteroptera: Miridae) is a zoophytophagous bug that can derive nutrients from 3 trophic levels: plants, herbivorous arthropods, and other predators. On tomato, besides damaging the plants as they feed, might the mirid also forage on pest species and repel pests. In greenhouse and laboratory experiments, we investigated the functional response of the bug, its prey preference, and its influence on the oviposition potentials of 2 major pest speciesHelicoverpa armigera(Hübner) (Lepidoptera: Noctuidae) andPhthorimaea absolutaMeyrick (Lepidoptera: Gelechiidae) on tomatoSolanum lycopersicumL. (Solanaceae).Nesidiocoris tenuisshowed a Type II functional response to both prey species. The estimated handling time was higher forH. armigeraeggs than forP. absolutayetN. tenuisattack rates did not differ between the 2 prey species.Nesidiocoris tenuisdid not show a preference for 1 species when prey eggs were provided in equal proportions. The feeding on tomato plants byN. tenuisdid not affect oviposition by the 2 moth species, as neither species showed a preference for clean orN. tenuis-adult-damaged plants and clean orN. tenuis-nymph-damaged plants. This study shows thatN. tenuiscan prey upon eggs of both moth species as the 3 species co-occur in tomato fields. However, because of the shorter handling time ofP. absolutaeggs by the predator and the higher number of eggs laid byH. armigera, the co-occurrence might be less detrimental to theH. armigerapopulations compared toP. absoluta.