This study examined the influence of superphosphate fertiliser application and sheep stocking rate on the density and diversity of soil macro- and mesofauna, particularly earthworms and oribatid mites in two sheep-grazed New Zealand hill pastures. The low-intensity (LI) long-term experimental farmlet is managed with no fertiliser and a low sheep stocking rate (9 stock units/ha); the high-intensity (HI) farmlet receives 34 kg P/ha/yr and has a high sheep stocking rate (16 stock units/ha). Soil mesofaunal samples were collected at two depths (0–7.5 cm and 7.5–15 cm). Earthworm species, major mesofaunal groups and oribatid species were identified, and the trophic groups, body size, biomass, mode of reproduction and global distribution of oribatid species established. Soil fertility, temperature, moisture, and pasture composition were also measured. The study tested the hypotheses that intensive pasture will have fewer native species, and among Oribatida, lower proportion of fungivores, higher proportion of asexuals, and higher proportion of smaller species with shorter life cycles. The results reflect the complex effect of intensive pasture management on soil organisms. Earthworm densities were higher in the intensive pasture system, with the exception of endemic Octochaetus multiporus. The low-intensity pasture system, where soil C:N ratio was wider, sheep stocking rate was lower and earthworm numbers were lower, supported higher density and diversity of soil mesofauna and Oribatida, which were concentrated in the topsoil (0–7.5 cm depth). In the high-intensity pasture system the zone of biological activity was expanded vertically—the mesofauna and Oribatida, although lower overall in density and diversity, were more evenly distributed between the 0–7.5 cm and 7.5–15 cm soil depths, suggesting reduced effect of livestock treading and greater food availability at depth. Pastoral intensification influenced oribatid trophic structure, with fungivorous species dominant in LI and herbofungivorous species in HI pasture, which probably reflected underlying differences in food resources, such as more fresh root biomass in HI. There was some evidence suggesting a shift to short-lived, cosmopolitan, and asexually reproducing Oribatida in HI at 0–7.5 cm soil depth. Oribatid density (which reflected mesofaunal densities), overall diversity, trophic groups, life-history characteristics and especially vertical distribution were more sensitive to soil management regime than their community structure.