ABSTRACT This treatment includes all species of pteridophytes known to occur naturally and those that have become naturalized in southeast Alabama. A total of seventeen families, twenty-nine genera, fifty-nine species, two varieties, and four hybrid taxa are known to occur in the study area. Dichotomous keys are provided for all families, genera, species, and three of the hybrids. A description is provided for the remaining two varieties and one hybrid. County level distribution maps and illustrations are provided for all species. The area delineated as southeast Alabama includes Barbour, Butler, Coffee, Conecuh, Covington, Crenshaw Dale, Escambia, Geneva, Henry, Houston, and Pike Counties. Distribution records are based upon specimens deposited in the Troy University Herbarium (TROY), J. D. Freeman Herbarium (AUA), The University of Alabama Herbarium (UNA), and University of West Florida Herbarium (UWFP).