Ballyoulster (Irish: Baile Ualstair)[2] is a village and townland located in County Kildare, Ireland.

Historically it lies within the barony of South Salt and the civil parish of Donaghcumper.

[3] For planning purposes, it is treated by Kildare County Council as a 'key development area' within the local area plan for the nearby town of Celbridge.

[1] Ballyoulster United is the local association football (soccer) club, which (as of 2015) was competing in the Leinster Senior League.

This article related to the geography of County Kildare, Ireland is a stub.