This is one in a proposed series of papers to present new data on the fungi of Louisiana. This paper includes descrs. of several new genera and spp. of parasitic fungi found in the state, in addition to new distr. and host records for several other spp. The new fungi are Microsphaera alni var. cinnamomi, on seedlings of Camphora cinnamomi Ramularia sidae on leaves of Sida sp. (including a collection from Florida); THALLOSPORA aspera on Veronica peregrina, infecting the entire plant and sporulating in the seed capsules; Ormathodium ambrosiae on leaves of A mbrosia trifida HELICOMINA caperoniae causing sooty spots on leaves of Caperonia castaneaefolia Ormathodium costaricense (Dendryphium c. Spegaz.) Thallospora is placed under the Staurosporae in Moniliaceae; Helicomina is placed with the Helicosporae in the Dematiaceae. Six other parasitic spp. are briefly discussed.