Clonsilla (Irish: Cluain Saileach, meaning 'meadow of the willow or sally tree') is an outer suburb of Dublin in Fingal, Ireland.

Clonsilla used to be a small village in the inner western part of County Dublin, but it is now a large residential suburban area, with Ongar and other localities developing their own subsidiary identities.

[citation needed] Luttrellstown Castle, dating from the early 15th century and once owned by members of the Guinness family, is now a hotel and golf course.

In November 1845, the canal near Clonsilla was the scene of an accident in which 15 people drowned, including two children, on a night boat to Longford.

[citation needed] Clonsilla is near the N3/M3 national road between Cavan and Dublin city centre.

Clonsilla is served by several Dublin Bus routes including the 39, the 39a and the L52 from Blanchardstown Shopping Centre.