Frank Kerlin was an Irish politician, and according to Dublin Made Me, the memoir of Todd Andrews, was deputy head of Republican intelligence during the Irish Civil War. "His signature 'K' became famous. The Staters never caught up with him," wrote Andrews, who added: "Had he lived, I think he would have been a major force in Irish politics. Kerlin died from TB before Fianna Fáil came to power."
He was elected to Dáil Éireann as a Fianna Fáil Teachta Dála (TD) for the Dublin South constituency at the September 1927 general election. He did not contest the 1932 general election.