Three fungal specimens (two sexual and one asexual) were collected during fieldwork conducted in China, Taiwan and Thailand. Both sexual morphs share superficial, black ascomata surrounded by flexuous setae; 8-spored, unitunicate, cylindrical asci, with J+, apical ring, and ellipsoidal to allantoid, aseptate, guttulate ascospores. The asexual morph has ceratosporium-like conidia arising from aerial hyphae with a single arm and are usually attached or with 2–3 arms, brown, often with a subglobose to conical cell at the point of attachment. Morphological examinations and phylogenetic analyses of a combined LSU-ITS dataset via maximum likelihood and Bayesian analyses indicated that these three collections were new species. Iodosphaeria chiayiensis (sexual morph), I. thailandica (sexual morph) and I. jinghongensis (asexual morph) are therefore introduced as new species in this study. Iodosphaeria chiayiensis has small, hyaline and ellipsoidal to allantoid ascospores, while I. thailandica has large ascomata, cylindrical to allantoid asci and hyaline to pale brown ascospores.