An annotated and updated checklist of the Iranian bryoflora is provided based on the published works and partly identification of collections available to the authors. A total of 437 taxa including 2 hornworts (Anthocerotopsida), 68 hepatics (Marchantiopsida and Jungermanniopsida) and 367 mosses (Bryopsida), within 149 genera and 57 families are known from Iran. This list includes 74 more taxa than the last checklist already published by Frey and Kürschner (1991). The most diverse genera of Iranian bryophytes are Amblystegium (9 taxa), Brachythecium (14 taxa), Bryum (28 taxa), Eurhynchium (12 taxa), Fissidens (14 taxa), Grimmia (13 taxa), Hypnum (9 taxa), Orthotrichum (11 taxa), Philonotis (15 taxa), Riccia (13 taxa), Schistidium (10 taxa), Syntrichia (15 taxa) and Tortula (15 taxa). The majority of species are known from humid provinces in the Northern parts of the country including Mazandaran with 246, Golestan with 143 and Gilan with 101 taxa, respectively. The bryological knowledge of different parts of Iran is not homogeneous. There are few bryological records or none for some provinces including Esfahan, Yazd,W Azerbaijan, Sistan va Baluchestan, Zanjan and Qazvin, Chaharmahal Bakhtiari and Kermanshah. Twelve new records for the country are added: Brachythecium campestre (Müll. Hal.) Schimp., Brachythecium oxycladum (Brid.) A. Jaeger, Cynodontium tenellum (Schimp.) Limpr., Entosthodon fascicularis (Hedw.) Müll. Hal., Grimmia elatior Bruch ex Bals.-Criv., Grimmia longirostris Hook., Gyroweisia tenuis (Hedw.) Schimp., Riccia fluitans L., Schistidium atrofuscum (Schimp.) Limpr., Tortula brevissima Schiffn., Tortula canescens Mont. and Weissia brachycarpa (Nees & Hornsch.) Jur. Nine species are excluded from the list of Iranian bryophytes, because of wrong records and Timmiella grosseserrata Schiffn. is considered as a synonym of Timmia megapolitana subsp. bavarica (Hessl.) Brassard .