Oud-Leusden is a hamlet in the Dutch province of Utrecht. It is a part of the municipality of Leusden, and lies about 4 km south of Amersfoort.
Oud-Leusden ("old-Leusden") was formerly just called "Leusden". The name is known from the year 776, when villa Lisaduna
was a large farm complex with defenses. Although it was assumed to be located near the current location of Oud-Leusden, no evidence of this complex has been found.
The church tower of Oud-Leusden is one of the oldest, perhaps the oldest, in the Netherlands. Originally it was part of a church, which before the reformation was dedicated to Saint Anthony. In the nineteenth century, most of the churchgoing population lived in the nearby village of Leusbroek (now Leusden-Zuid), and the church was repplaced with a new one in Leusbroek, and demolished in 1828.