The effect of different atmospheric CO2 concentrations on life table parameters and the biology of the cabbage aphid, Brevicoryne brassicae, when fed on two cultivars of ornamental cabbage, was studied in a greenhouse designed for CO2 studies. Aphid performance was influenced by increasing atmospheric CO2 levels, significantly affecting the intrinsic rate of increase (Gamma(m)), finite rate of increase (lambda), mean generation time (T), doubling time (DT), and pre-reproductive period. The longest pre-reproductive period was observed for aphids grown at 380 ppm CO2. The intrinsic rate of natural increase was highest for aphids at 1050 ppm CO2, because of their faster development, high daily rate of progeny production, and higher survivorship. Future elevated CO2 concentrations will enhance aphid population outbreaks and consequently increase the damage caused. (C) Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, 2012. Published by Elsevier B.V. All rights reserved.