Mark Killilea Snr (15 January 1897 – 29 September 1970) was an Irish Fianna Fáil politician.

[5] He took his seat in the 5th Dáil, along with the 44 other Fianna Fáil TDs who ended the Republican policy of abstentionism and took the disputed oath of allegiance, dismissing it as an "empty formula".

[6] At the 1961 general election, he lost his seat again, this time in the restored Galway East constituency.

[7] In 1958 Killilea and his wife fostered Anne Silke, a former resident of the Tuam Mother and Baby Home.

Before she died Anne Silke gave evidence reported in the 2021 documentary Untold Secrets produced by Nova Productions and directed by Basque filmmaker Teresa Lavina that she was beaten and abused while in the family's care and used as little more than a slave.