Abstract: To determine the relationship between the oviposition preference of the adult and the feeding preference of the larvae between Helicoverpa armigera and H. assulta, we tested the olfactory response and feeding response of the larvae and the oviposition preference of the adults of both Helicoverpa species to Nicotiana tabacum and N. rustica under choice and non-choice conditions. The results of the olfactory response of the larvae indicated that the fifth instar larvae of H. armigera and the first instar larvae of H. assulta showed significant preference to N. rustica than to N. tabacum, while the other instar larvae could not distinguish between N. rustica and N. tabacum. In the feeding response test, H. armigera larvae preferred to feed on N. tabacum, while H. assulta larvae preferred to N. rustica under choice condition. However, under non-choice condition, N. tabacum was selected for feeding by larvae of both species. The oviposition preference response of H. armigera to N. rustica showed slightly higher than to N. tabacum, but not significantly, while H. assulta had a remarkable oviposition preference to N. rustica. In conclusion, the oviposition preference of both Helicoverpa species was in correspondence with its feeding preference of the larvae to both tobacco species, this phenomenon accords with "Preference-performance hypothesis "for host selection of insects.