Leixlip ( or ; Irish: Léim an Bhradáin) is a town in north-east County Kildare, Ireland, near Dublin. Its location on the confluence of the River Liffey and the Rye Water has marked it as a frontier town historically: on the border between the ancient kingdoms of Leinster and Brega, as an outpost of The Pale, and on Kildare’s border with County Dublin. Leixlip was also a civil parish in the ancient barony of Salt North.
As of 2016, the population of the town was 15,504. It is the fourth largest town in Kildare, and the 29th largest in Ireland.