As drylands expand due to climate change and unsustainable land use (e.g. overgrazing), understanding dry ecosystems is ever so important. In drylands, macro-detritivores (e.g. termites and woodlice) play a crucial role in plant litter decomposition compared to microorganisms, due to better adaptability to dry conditions. We hypothesized that large herbivore grazing, a major land use in drylands, affects macro-detritivore contribution to decomposition through effects on the plant community and the physical environment. Our results show grazing facilitates macro-detritivore contribution to decomposition via effects on the plant community. These findings suggest interactions between grazing, plant community composition and decomposer size are significant to elemental cycling in drylands.