Erie Bluffs State Park in Erie County, Pennsylvania, established in 2004, occupies 219 ha along 2.25 km of Lake Erie shoreline. The park is notable for its highly erodible lakeshore bluffs, black oak sand barrens, and lakeplain swamp forests. A vascular plant inventory was undertaken and supplemented with historical collections to provide a vouchered checklist from the site now occupied by Erie Bluffs State Park. A second checklist with a list of unconfirmed records is based on unvouchered sightings from the park and specimen records from the vicinity of the park that cannot confidently be mapped within the park boundaries. The checklist includes 555 vascular taxa in 309 genera and 98 families with taxa representing the following groups: Equisetophyta (5), Lycopodiophyta (4), Pteridophyta (22), Coniferophyta (3), Liliopsida (136), and Magnoliopsida (385). Poaceae (56 species), Asteraceae (56 species), Cyperaceae (41 species), Rosaceae (36 species), and Brassicaceae (22 species) are the five largest families. The flora includes 391 species and subspecific taxa listed as native to Pennsylvania, and 159 that are introduced; the remaining five species are of uncertain native status. Twenty-three species are listed as species of concern, 19 represent Erie County records, and three are new to the flora of Pennsylvania. An additional 108 species are reported as unconfirmed records needing further inventory work. Plant communities are mapped and described. The vascular plant species of Erie Bluffs State Park are found among 14 natural communities and anthropogenic cover types, including 4 natural communities limited to the Great Lakes Region: Great Lakes Region Scarp Woodland; Great Lakes Bluff Seep; Elm–Ash–Maple Lakeplain Forest; and Black Oak Barrens.