Hassea is a genus of fungi in the class Dothideomycetes.
The relationship of this taxon to other taxa within the class is unknown (incertae sedis).
[1] A monotypic genus, it contains the single species Hassea bacillosa.
[2] The genus name of Hassea is in honour of Hermann Edward Hasse (1836–1915), who was an American lichenologist.
[3] The genus was circumscribed by Alexander Zahlbruckner in Beih.