The tobacco aphid, Myzus nicotianae Blackman, is a major pest of tobacco in the United States. It was separated from the green peach aphid, M. persicae (Sulzer), and described as a new species in 1987. Information on its host range is limited because the two species are so similar. Therefore, the performance of the tobacco aphid was studied on 28 potential host plants in six families. Numbers of offspring, age at first reproduction, longevity, weight, and percentage reproducing were compared. Tests were conducted on excised leaves or leaf disks maintained in Petri dishes in an environmentally-controlled chamber. Myzus nicotianae reproduced on hosts in the families Asteraceae, Convolvulaceae, Cruciferae, Malvaceae, and Solanaceae, but not on Spinacia in Chenopodiaceae. Myzus nicotianae generally reproduced most quickly, was heaviest, and produced the most nymphs on tobacco, Nicotiana tabacum L., and American black nightshade, Solanum americanum (Solanaceae). Performance also was good on Capsicum and S. dulcamara L. (Solanaceae). Aphids exhibited fair-to-good performance on three species of Ipomoea (Convolvulaceae), Datura, and Physalis (Solanaceae); Raphanus and two species of Brassica (Cruciferae); and Abelmmoschus (Malvaceae). Performance was fair on two species of Ipomoea, three species of Solanum, Lactuca (Asteraceae), and several Brassica. Longevity was short, and very few offspring were produced on Gossypium (Malvaceae) and Lycopersicon (Solanaceae). This study indicates that M. nicotianae does well on several species in five plant families that contain important crop and weed species.