<p>Glaciers are significant components of Earth’s biomes, functioning as ecosystems and shaping adjacent systems. The retreating glaciers form ice-free areas on their forefields, which become colonized by pioneering organisms. Although these dynamic ecosystems are investigated worldwide, the diversity, distribution, and role of mites (Acari) in newly deglaciated areas remain virtually unknown, with few studies published to date. In this study, the diversity of acariform mites (Prostigmata and Endeostigmata) in glacier forefields and moraines of European and Arctic glaciers was investigated for the first time. Soil and vegetation samples were collected from Spitsbergen (Svalbard), the Alps, and the Pyrenees. Prostigmatic and endeostigmatic mites were present in all sampling sites. Collectively, 34 species were found, including 29 species of Prostigmata and five species of Endeostigmata. This dominance of Prostigmata over Endeostigmata reflects a much higher global diversity of the former. The two prostigmatic superfamilies, Eupodoidea and Tydeoidea, were the most species-rich in the examined material. Representatives of both groups are known from harsh, cold environments and have the potential to be pioneer fauna and the first faunal component of trophic webs in forefields and moraines. This study demonstrates that Prostigmata and Endeostigmata are surprisingly diverse in the forefields and moraines. Due to their diverse diet, they can play important roles in food webs during post-glacial forefield succession and thus should not be overlooked in ecological studies.</p>