Daniel John O'Donoghue (August 1, 1844 – January 16, 1907) was a printer, labour leader and political figure in Ontario.

The working class community was sharply divided between the Irish and French Canadian workers, but O'Donoghue helped personally bridge this gap through his marriage to Marie Cloutier.

O'Donoghue's candidacy was made possible by the recent decision by Oliver Mowat's government to remove the property qualifications on running for office.

[2] Facing concerted opposition from both the Liberals and Conservatives, he lost in most of the city, but won a massive majority in the working-class neighbourhoods of Lowertown.

By the next election things had changed, as a deep recession had deeply wounded the labour movement in Ottawa, O'Donoghue finished third.

He also helped convince the leaders of the Roman Catholic Church in Canada to accept rather than oppose a new international labour organization, the Knights of Labor.