Peatlands are unique and complex ecosystems of global significance, essential for biodiversity conservation and for maintaining key ecological functions such as carbon storage, water retention, and water purification. These functions have become especially critical in the context of contemporary global change, including rising CO2 emissions, increasing water scarcity, and accelerating biodiversity loss—three of the most urgent environmental challenges facing humanity today. Although Sphagnumdominated peatlands are often considered species-poor due to their waterlogged and acidic conditions, they support rich and abundant communities of Oribatida mites, including numerous habitat specialists rarely found elsewhere. This study provides baseline knowledge on the diversity of Oribatida mites in Norwegian peatlands, offering a foundation for evaluating peatland degradation and guiding future restoration efforts. Norwegian peatlands were investigated between 2020 and 2023 as part of a project funded by the Norwegian Taxonomy Initiative. Samples of Sphagnum mosses were collected in Atlantic raised bogs—ecosystems that are rare and largely destroyed across Europe but remain relatively intact in many Norwegian regions, although they are increasingly threatened. Sampling was carried out in six peatlands in nearly pristine condition, located across southern, central, and northern Norway, providing a broad geographical representation. In addition to the newly collected material, historical specimens stored in the University Museum of Bergen were also examined. Oribatida mites occurred in very high abundances, averaging approximately 50,000 individuals per square meter, and strongly dominated the mite assemblages, accounting for about 97% of all specimens collected. Species richness was also high: in total, around 150 oribatid species were recorded, many of them restricted to peatland habitats. The material included 19 species newly recorded for Norway and three species new to science. Juvenile stages constituted nearly 40% of all oribatid specimens, highlighting the importance of including them in analyses to fully understand peatland diversity and ecological processes. The mite communities also showed clear vertical stratification within the Sphagnum layers, and more than 20% of the species were found exclusively in deeper layers. These findings emphasize that sampling deeper peat layers is essential for accurately assessing the full diversity of oribatid mites in peatland ecosystems.