Portneuf-sur-Mer (French pronunciation: [pɔʁnœf syʁ mɛʁ]) is a municipality in the Côte-Nord region of the province of Quebec in Canada. The municipality is located at the mouth of the Portneuf River on the St. Lawrence River.

The municipality was known as Sainte-Anne-de-Portneuf prior to January 31, 2004.

Around 1500, this place was already visited by Basques whalers and sealers, who may have named it after Port-Neuf near Bayonne in Basque Country. It was mentioned by Samuel de Champlain in 1626 as "Port neuf", and François de Crespieul held his first mass there in 1683. A trading post existed there at the end of the 17th century. In 1788, a chapel was built at the mouth of the Portneuf River and dedicated to Saint Anne.

Permanent settlement began in around 1845, and the community had several names over time: Saint-Georges in 1848 (after the surveyor Georges Duberger), Portneuf Mills in 1882 (due to the presence of a mill), and Hamilton Cove in 1883 (named after a forestry company). This last name was also chosen for the post office. The Innu called the location Mitinekapitsh or Mitinakup.

In 1875, the parish of Sainte-Anne-de-Portneuf was founded. In 1902, the place was incorporated as the United Township Municipality of Sainte-Anne de Portneuf, when it split off from the Township of Saint-Paul de Mille-Vaches (now part of Longue-Rive). In 1949, the post office was renamed to Portneuf-sur-Mer.

On January 1, 1950, it lost part of its territory when the Municipality of Saint-Luc-de-Laval was created (which was annexed into Forestville in 1980). On July 16, 1955, the united township municipality changed statutes and became a regular municipality. On January 31, 2004, it was renamed to Portneuf-sur-Mer.

Historical Census Data - Portneuf-sur-Mer, Quebec

Year Pop. ±% 1921 428 —     1931 903 +111.0% 1941 2,011 +122.7% 1951 1,051 −47.7% 1956 1,386 +31.9% 1961 1,521 +9.7%	Year Pop. ±% 1966 1,496 −1.6% 1971 1,393 −6.9% 1976 1,303 −6.5% 1981 1,255 −3.7% 1986 1,115 −11.2% 1991 1,032 −7.4%	Year Pop. ±% 1996 990 −4.1% 2001 922 −6.9% 2006 835 −9.4% 2011 761 −8.9% 2016 641 −15.8% 2021 612 −4.5%
2016 Population figure based on revised count. Population counts are not adjusted for boundary changes. Source: Statistics Canada

Private dwellings occupied by usual residents (2021): 321 (total dwellings: 357)

Mother tongue (2021):

• English as first language: 0%
• French as first language: 100%
• English and French as first language: 0%
• Other as first language: 0%

List of former mayors:

This list is incomplete; you can help by adding missing items. (July 2024)

• Alcide Tremblay (1940–1941)
• Albertus Bouchard (1941–1943)
• Alcide Tremblay (1943–1957)
• Gilles Tremblay (1957–1958)
• Alcide Tremblay (1959–1961)
• Jules Ouellet (1961–1963)
• Alcide Tremblay (1963–1964)
• Benoit Gagnon (1964–1966)
• Adélard Maltais (1966–1967)
• Alcide Tremblay (1967–1973)
• Clarisse Miller Gagnon (1973–1977)
• Renaud Desmeules (1977–1985)
• Jean-Marie Delaunay (1985–2013)
• Gontran Tremblay (2013–2021)
• Jean-Maurice Tremblay (2021–present)

• Hugo Girard, strongman

• List of municipalities in Quebec

• Official website