Ballaghkeen South (Irish: An Bealach Caoin Theas) is a historical barony in southwest County Wexford, Ireland.

[2][3] The barony takes its name from Ballaghkeen (The Ballagh), a village in County Wexford.

The McMurphys of Uí Felmeda Thes ("Southern Descendants of Felmed") are noted very early here.

[4] The single barony of Ballaghkeen was created in 1606; it was divided into north and south some time before 1868.

[5][6] Ballaghkeen South is in the eastern coastal part of the county, east of the River Slaney and north of Shelmalier.