John O'Flaherty (June 17, 1821December 26, 1886) was an Irish American immigrant and farmer. He served one term in the Wisconsin State Assembly (1879), representing southern Brown County.
O'Flaherty was born on June 17, 1821, in Tralee, Ireland. He later moved to Morrison, Wisconsin. He died at Stark in the town of Morrison on December 26, 1886.
O'Flaherty was elected to the assembly as a representative of Brown County's 3rd district in 1878. He was a Democrat.
| colspan="6" style="text-align:center;background-color: #e9e9e9;"| General Election, November 5, 1878