| John Dinneen | |
| Office: | Teachta Dála |
| Term Start: | August 1923 |
| Term End: | June 1927 |
| Constituency: | Cork East |
| Term Start2: | June 1922 |
| Term End2: | August 1923 |
| Constituency2: | Cork East and North East |
| Party: | Farmers' Party |
| Birth Date: | 23 March 1867 |
| Birth Place: | County Cork, Ireland |
| Death Place: | County Cork, Ireland |
John Dinneen (23 March 1867 – 1 January 1942) was an Irish Farmers' Party politician. A farmer, he was first elected to Dáil Éireann at the 1922 general election as a Farmers' Party Teachta Dála (TD) for the Cork East and North East constituency.[1] He was re-elected at the 1923 general election for the Cork East constituency. He lost his seat at the June 1927 general election.[2]
His nephew Liam Ahern served as a Fianna Fáil Senator and TD from 1957 to 1974 and his grand-nephew Michael Ahern, son of Liam Ahern, has been a Fianna Fáil TD for Cork East from 1982 to 2011.[2]
In June 1922 the Bishop of Cloyne Robert Browne, contributed £20 each to the election funds of Michael Hennessy and Dinneen, Commercial and Farmer pro-Treaty candidates respectively for the Cork East and North East constituency.[3]