Presented is an annotated catalog of the 38 genera and 382 species of Leiodidae known to occur in the Nearctic Region of North America north of Mexico (the continental USA and Canada). Information on types, distributions, and biologies is included. Twelve of the species also or probably occur in Mexico, and 16 of the species also occur in Europe and/or Asia (i.e., are Holarctic in distribution). Ptomaphagus (Appadelopsis) neojonesi Peck and Newton is proposed as a nomen novum (replacement name) for Ptomaphagus (Adelops) jonesiPeck, 1978, preoccupied by Ptomaphagus valentinei jonesiJeannel, 1949. Stereus arenariusPeck and Cook, 2009 is transferred to Pseudotriarthron as P. arenarium (Peck and Cook, 2009), new combination.