To compare carabid assemblages from transgenic Bt- and isogenic maize in Hungary, we used pitfall traps in an experiment (30x30 m plots, arranged alternately in 6 replications), during the growing season of maize during 2001-2003.  We captured altogether 44,103 individuals of 58 species.  The most common species in our sampling were Calathus ambiguus, Dolichus halensis, Harpalus distinguendus, H. rufipes, Poecilus sericeus and Trechus quadristriatus.  The same species dominated both in the Bt- and in the isogenic maize plots.  Under our test conditions (plot size and 3 years of sampling), no significant differences were found either in the structural characteristics (number of individuals, number of species and diversity), activity density or seasonal activity patterns of the dominant species.