Here, the abundance of macro-invertebrates (Arthropoda and Gastropoda) of eight green roofs and their adjacent ground level habitats in the city of Antwerp, Belgium, is compared. All higher-level taxa found were present in both types of habitats without significant differences in their overall abundance between green roofs and ground level habitats. However, we found significant differences in abundances between the two types of habitats, when specific taxa were compared. Beetles (Coleoptera), isopods (Isopoda) and bees (Anthophila) were more abundant at ground level sites compared to green roofs, while for true bugs (Heteroptera) and cicadas (Auchenorrhyncha) the opposite was found. Our results support the idea that extensive green roofs in Belgium can provide a suitable habitat for different invertebrate taxa, but further research is needed to identify the true drivers behind differences in abundance between ground level and adjacent green roofs.