Three new species of Pseudotaeniacanthus Yamaguti & Yamasu, 1959 were discovered infesting gill filaments of the laced moray, Gymnothorax favagineus Bloch & Schneider, caught off southern Taiwan. Two of these species, P. dentiferus, new species and P. similis, new species, are distinguished from their congeners by the presence of a tooth-like projection on the ventral side of the proximal segment of their antennule. Pseudotaeniacanthus similis differs from P. dentiferus in having a plumose seta (instead of a spine) on the outer margin of the terminal, endopodal segments of legs 2–4. The third species, P. conspicuus, new species, is distinguished by the presence of a rostral bar partially visible in dorsal view and a small protuberance on the posterolateral margin of the cephalothorax. A key to the 11 species of Pseudotaeniacanthus is provided.