Coprinoid mushrooms grown on wood of broad-leaf species were collected for the first time in Armenia and dikaryotic mycelial cultures were established. ITS (internal transcribed spacer) sequences identified one species as Coprinopsis strossmayeri and the other as a species closely related to Coprinellus radians. Mycelial growth and morphological features on different media are described. The pearl-white-silky colonies of C. strossmayeri are characterized by mycelial strands and by a light-yellow agar colorization. The species forms chlamydospores intercalary in its hyphae. Some hyphal ends form hyphal loops. Colonies of C. aff. radians have a characteristic yellow pigmentation and stain the agar yellowish. Hyphae are mostly clampless but at some septa, pseudoclamps are seen from which side-branches develop growing along the parental hyphae. In the mycelium of C. aff. radians, hyphal loops, hyphal swellings, cystidia and typical allocysts were observed. Both new species from Armenia show growth optima at temperatures of 25 to 30 °C and pHs of 6.0 to 7.0. Both grow in alkaline conditions up to pH 12.0 but not at pHs 3.0 and 4.0, classifying them with other coprinoid mushrooms as “ammonia fungi”. Both species grew on a variety of lignocellulosic substrates and both show polyphenol oxidase activities.