The Confederation Line, also called O-Train Line 1, is a light rail line operated by OC Transpo in Ottawa, Ontario, Canada, as part of the city's O-Train light rail system. It opened on September 14, 2019, and is O-Train's second line. It operates on an east–west route, with a segment under Queen Street in the downtown core, complementing the north–south Trillium Line that operates to the west of the downtown core. Using light rail rolling stock and technology, the Confederation Line is completely grade separated.

OC Transpo is the organisation that operates and plans public transport in the city of Ottawa. OC Transpo's system includes bus rapid transit, light rail, conventional bus routes, and door-to-door paratransit.