Perithecia in Pyricularia sp. from Eleusine coracana(L) Gaertn. were obseryed by using a scanning electron microscope. Perithecia appeared on a culture medium about 15 days after mating. At 30-days-old culture, perithecia were usually wholly embedded, with long beaks protruding from the surface of medium. Ostiole such as that seen in Pyrenomycetes was not observed at the top of beak. However, when perithecial beaks were cut longitudinally or clossly, ostiole-like canals were observed. The coriaceous perithecium was composed of pseudoparenchyma, and was 9-14μm thick, with an inner layer of large angular cells(4-8×4-10μm) and an outer layer of small globular cells. Some times, asci or ascospores released were observed in a cavity of mature perithecia Asci were cylindrical to subclavate and had arised from the base of the perithecium, and its surface was smooth.