Data on the representatives of the nematode family Rhabdiasidae in the Nearctic are summarized from the literature, study of new material, and examination of museum specimens. A description of Rhabdias tarichae sp. nov. and redescriptions of Rhabdias joaquinensis, Rhabdias ambystomae, Rhabdias ranae, and Rhabdias americanus are given. New host and geographical records are provided for several Rhabdias species. Rhabdias sp., probably representing another species new to science, was found among museum specimens from the California newt Taricha torosa; however, the poor state of the specimens did not permit description. Keys for determination of Nearctic Rhabdias species are provided, and the applicability of some morphological characters for differentiation of Rhabdias species is discussed.