Niagara was a federal electoral district in the Canadian province of Ontario, which was represented in the House of Commons of Canada from 1867 to 1883. It is sometimes also considered one of Ontario's historic counties, as it was listed in some post-Confederation census records as a county of residence.

Niagara consisted of the Lincoln County townships of Niagara and Grantham, including the towns of Niagara-on-the-Lake and St. Catharines.

The electoral district was abolished in 1882 when it was merged into Lincoln and Niagara riding.

This riding has elected the following members of Parliament:

On election being declared void:

On election being declared void:

Mr. Hughes was disqualified; subsequently the Court struck off four votes from Mr. Hughes' list for bribery, thus giving the seat to Mr. Plumb by a majority of two.

• Library of Parliament website