The springtail (Hexapoda: Collembola) fauna of eight caves (Wizard Cave, Pautler Cave, Spider Cave, Wanda’s Waterfall Cave, Illinois Caverns, Stemler Cave, Hidden Hand Cave, and Bat Sump Cave) in the Salem Plateau of southwestern Illinois (Monroe and St. Clair counties) was surveyed in 2009 using a combination of methods, including pitfall traps, Berlese-funnel processing of litter, and hand collections by quadrat, on drip pools, free standing bait, and random locations. In total, forty-nine species of springtails were found. Four are described as new to science (Onychiurus pipistrellae n. sp., Pygmarrhopalites fransjanssens n. sp, P. incantator n. sp, and P. salemensis n. sp), four may represent new species but there is insufficient material available to prepare full descriptions (two species in the genus Superodontella, one in Pseudachorutes, one in Sminthurides), and three others (Ceratophysella cf. brevis, C. cf. lucifuga, and Folsomia cf. bisetosa) are identified to species, but differences from the nominal species suggest further studies may indicate the Illinois populations represent distinct forms. In addition, five other species represent new records for Illinois, and eighteen are new cave records for the species in North America. The new records more than double the number of springtails species known from caves in the Salem Plateau region. More than half (twenty-nine) of the species reported are ranked as rare (S1–S2) at the state level. The total number of springtail species in Salem Plateau caves could be more than twice what is recorded in the present study, and more new species and state records should be found when caves in other Illinois karst regions are more thoroughly examined.