Thirty seven species of lichenicolous fungi are reported from southern Siberia. Sagediopsis vasilyevae (on Rhizocarpon inarense) is described as new to science. Rosellinula haplospora is new to Russia. Abrothallus peyritschii, Arthonia apotheciorum and Lichenostigma cosmopolites are new to Siberia. Cetraria is a new host genus for Stigmidium microcarpum. Ameroconium cladoniae and Plectocarpon hypogymniae are newly documented on Cladonia alaskana and Hypogymnia tubulosa correspondingly.