Wild bees (Hymenoptera, Apoidea, Anthophila) and syrphids (Diptera, Syrphidae) associated with urban green roofs in the canton of Geneva. − Wild bees and syrphids were sampled in 2017 on six extensive urban green roofs in the canton of Geneva (Switzerland) using cornet and emergence traps. Sixty-two species of wild bees (Hymenoptera) and ten species of syrphids (Diptera) were sampled. Of the species caught, fourteen species of wild bees and three species of syrphids are considered threatened in Switzerland. The first mention of Hylaeus leptocephalus in the canton was recorded. A selection of these species is discussed in detail. Our findings highlight the potential of green roofs to promote arthropod diversity in an urban context.