Data was collected from 45 monthly samples at three vegetation layers spanning from 1950 to 2500 meters above sea level in the Arjan Plain Biosphere Reserve, Fars Province, Iran. A total of 12,648 individuals were collected, leading to the identification of 89 species of oribatid mites from 39 families and 53 genera The data for the Shannon diversity index was analyzed using the permutation one-way analysis of variance (PERMANOVA) to understand the distribution of mites across the elevation gradients. Significant variations were observed in the distribution of oribatid mites at different elevational strata. Layer 2 exhibited the highest species richness and total abundance of oribatid mites, with 67 species and 6162 individuals, followed by layer 3 with 62 species and 4359 individuals, and layer 1 harbouring 59 species and 2140 individuals. Dominant species included Jacotella frondeus (Kulijev) and Oribatula pallida Banks in layer 1, Pilogalumna tenuiclava (Berlese), Aleurodamaeus sp.3, and J. frondeus in Layer 2, and Aleurodamaeus sp.3 and J. frondeus in layer 3. The Shannon index also revealed that species diversity of oribatid mites significantly increased with elevation increase. Furthermore, the analysis indicated a notable seasonal effect on oribatid mite biodiversity, demonstrating the lowest species richness and abundance observed in July and September.