Order Mesostigmata is one of the largest groups in subclass Acari and its members are important components of natural and agricultural ecosystems. During 2013, fauna of edaphic mesostigmatic mites were collected from soil and plant debris of Arasbaran forests in north of East Azerbaijan province, Iran. Mites were extracted by using Berlese funnels, cleared in Nesbitt's fluid and slides mounted by Hoyer's medium. In this study, 40 species belonging to 32 genera and 18 families were collected and identified. Among the identified species, 20 species were new for East Azerbaijan province fauna. A key for identified taxa has been given. In this study, the family Veigaiidae had the highest relative frequency (19. 01%) and the families Zerconidae and Laelapidae with 15. 21% and 13. 19 frequencies were situated in the next ranks, respectively. The list of identified species are as follows. New records for East Azerbaijan Province mites fauna are marked with one asterisk (*): Ameroseiidae: Ameroseius furcatus (Karg, 1971)*, Epicriopsis cf. palustris (Karg, 1971); Ascidae: Zerconopsis michaeli (Evans & Hyatt, 1960)*, Arctoseius semiscissus (Berlese, 1892)*, Asca aphidioides (Linnaeus, 1758)*, A. bicornis (Canestrini & Fanzago, 1876)*, Antennoseius bacatus (Athias-Henriot, 1961)*; Blattisocidae: Lasioseius sp.; Celaenopsidae: Celaenopsis badius (C. L. Koch, 1839)*; Digamasellidae: Dendrolaelaps sp.; Epicriidae: Epicrius cf. bulgaricus (Balogh, 1958); Laelapidae: Laelaspis astronomicus (Koch, 1839), Cosmolaelaps lutegiensis (Shcherbak, 1971), C. vacua (Michael, 1891), Gaeolaelaps aculeifer (Canestrini, 1884), G. iranicus (Kavianpour & Nemati, 2013), Pseudoparasitus dentatus (Halbert, 1920)*, P. missouriensis (Ewing, 1909)*; Macrochelidae: Macrocheles glaber (Mü ller, 1860)*, Macrolaspis recki (Bregetova & Koroleva, 1960); Macrodinychidae: Macrodinychus bregetovaae (Hirschmann, 1975)*; Melicharidae: Proctolaelaps pygmaeus (Mü ller, 1860)*; Pachylaelapidae: Olopachys caucasicus (Koroleva, 1976)*, Onchodellus karawaiewi (Berlese, 1920)*; Parasitidae: Gamasodes spiniger (Trä gå rdh, 1910)*, Parasitus copridis (Costa, 1963)*; Phytoseiidae: Amblyseius azerbaijanicus (Abbasova, 1970), A. nemorivagus (Athias-Henriot, 1961), A. sp., Typhlodromus bakeri (Garman, 1948); Trachytidae: Trachytes cf. aegrota (C. L. Koch, 1841)*; Trematuridae: Trichouropoda elegans (Kramer, 1882)*, T. ovalis (Koch, 1839)*, Nenteria stylifera (Berlese, 1904)*; Uropodidae: Discourella modesta (Leonardi, 1899), Uropoda fumicola (Schweizer, 1961); Veigaiidae: Veigaia nemorensis (Koch, 1836), V. planicola (Berlese, 1882); Zerconidae: Prozercon norae (Ujvari, 2011), Zercon sp.