Plantation forests constitute a large proportion of the forest estate in many countries, particularly in the temperate regions of Europe. In addition, large scale deforestation has led to the fragmentation of natural forests within heavily managed agricultural landscapes. In light of this, it is important that the potential of plantations to support a diverse flora and fauna, particularly for forest specialist species, is assessed. We examined arthropod diversity in mixed and single species plantations of non-native conifers and native woodlands in Ireland to assess the potential of plantations to support forest species. Spiders and Carabid beetles were sampled with pitfall traps and moths with light traps among forest types. Environmental parameters measured included stand structure, soil attributes, plant richness and forest cover. Invertebrate species composition and richness differed between plantations and native woodlands, but responses also differed by taxonomic group. At the stand scale invertebrates were related to litter and vegetation cover, and forest type, but variables at the landscape scale (e.g. forest cover within 1km) were only important for moths. These findings suggest that forest policy aimed at promotion of biodiversity in plantations should support greater diversity of stand structure and tree species composition. The planting of more species of native provenance should also be encouraged