Oisín Kiernan (born 1 October 1992) is an Irish Gaelic footballer who plays for the Cavan county team.

[9] On 1 April, Kiernan was in the half back line as Cavan faced Roscommon in the National League Division 2 Final.

On 24 March 2019, Kiernan featured as a substitute against Dublin in the National League,[12] and started the Ulster quarter-final win over Monaghan on 19 May.

[15] On 22 November 2020, Kiernan was in the half-forward line as Cavan faced Donegal in the Ulster Final for the second year in a row.

[16] On 5 December, Kiernan started the All-Ireland semi-final, scoring two points in the loss to eventual champions Dublin.

He had found a lump a month earlier, but didn't get it looked at because he wanted to keep playing football, a decision he later regretted.