Leighlin

Leighlin may refer to:


 * Old Leighlin, medieval town in County Carlow, Ireland
 * Leighlinbridge, nearby modern town
 * Old Leighlin (Parliament of Ireland constituency), abolished 1800
 * Bishop of Leighlin, former Christian diocese in Ireland
 * Baron Brereton of Leighlin, title in the Peerage of Ireland 1624–1722