Two new species of freshwater sculpins are herein described from the Gulf Slope of the southeastern United States. The Tallapoosa Sculpin, Cottus tallapoosae, is restricted to the Tallapoosa River drainage, a tributary to the Mobile Basin, above the Fall Line in Alabama and Georgia, while the Chattahoochee Sculpin, Cottus chattahoochee, is restricted to the Chattahoochee River drainage, a tributary to the Apalachicola River, above the Fall Line in Georgia. Both differ from other North American sculpins primarily in having modally eight infraorbital canal pores and five suborbitals (otherwise shared only with Cottus paulus). Cottus tallapoosae and C. chattahoochee differ from each other primarily with the former having an incomplete lateral line and reduced or absent post-pectoral prickling, whereas the latter usually has a complete lateral line and a well-developed postpectoral patch. Cottus tallapoosae is the sixth species of fish endemic to the Tallapoosa River drainage, while Cottus chattahoochee is the eighth species endemic to the Apalachicola River drainage. Both species are widespread above the Fall Line and locally abundant. They typically inhabit rocky shoals and riffles of small upland streams, but are occasionally found in larger rivers.