Ophiocordycepsis entomopathogenic and the largest studied genus in the familyOphiocordycipitaceae. Many species in this genus have been reported from Thailand. The first new species introduced in this paper,Ophiocordycepsglobiceps, differs from other species based on its smaller perithecia, shorter asci and secondary ascospores and additionally, in parasitising fly species. Phylogenetic analyses of combined LSU, SSU, ITS, TEF1α and RPB1 sequence data indicate thatO.globicepsforms a distinct lineage within the genusOphiocordycepsas a new species. The second new species,Ophiocordycepssporangifera, is distinguished from closely related species by infecting larvae of insects (Coleoptera, Elateridae) and by producing white to brown sporangia, longer secondary synnemata and shorter primary and secondary phialides. We introduceO.sporangiferabased on its significant morphological differences from other similar species, even though phylogenetic distinction is not well-supported.