Some Setaria spp., such as S. digitata, S. marshalli, S. marshalli pandei, S. equina and S. labiatopapillosa were studied by scanning electron microscopy at the critical points in the anterior and posterior parts of the adult worms. The amphids, Deirids, find transverse striations of the cuticle and phasmidial pare, as well as the transverse bands (lugae), postdeirid and ventral papillae (only of the male) were visualized clearly at this examination. They contribute towards the identification of Setaria spp., in addition to the characteristics which are demonstrated by common light microscopy.