Cladonia wainioi has greenish to brownish mineral-grey podetia that are covered with small scales. The axils are open. Pycnidia are common, while apothecia are rare. Cladonia wainioi is highly branched, and similar in form to the common speciesCladonia multiformis and Cladonia furcata. The latter two species, however, have a lichen spot test of PD+ red, while C. wainioi is PD−.