Marsoui is a village municipality in the Gaspésie–Îles-de-la-Madeleine region of Quebec, Canada.

The name Marsoui is thought to originate from the Mi'kmaq word malseoui, meaning "flint" which is abundant in the area. However, another theory explains that it comes from the French word marsouin, the vernacular term for porpoise or beluga whale that used to be present in the Gulf of Saint Lawrence in large numbers. Alternate spellings used over time were Marsouis, Marsoin, and Marsouins.

While the beluga hunt and cod fishing was popular in this area during the late 17th century, it was not until 1836 that the first permanent settlers, the Henley family of Mont-Louis, arrived. They were followed by people from Jersey.

In 1890, the Mission of Sainte-Émélie-de-Marsoui was founded there, and 3 years later, the local post office opened. Subsistence fishing was the main economic activity until 1911. Then a small saw mill was built that started the transformation to a forestry-based economy. Over the following decades, several saw mills burnt down and were rebuilt.

During the Prohibition era in the United States, Marsoui was a favorite hideout for smugglers fleeing the Royal Canadian Mounted Police.

In 1923, the villages of Marsoui and Rivière-à-la-Marthe separated from the municipality of Sainte-Anne-des-Monts to form the Township Municipality of Christie. In turn, Marsoui separated from this township in 1950 to be incorporated as a village municipality. Its first mayor was Alphonse Couturier, whose company had built a large saw mill in Marsoui in 1940.

From 1945 to 1954, a lead and zinc mine operated about 21 kilometres (13 mi) southwest of Marsoui.

In the 2021 Census of Population conducted by Statistics Canada, Marsoui had a population of 289 living in 149 of its 179 total private dwellings, a change of 5.1% from its 2016 population of 275. With a land area of 181.4 km (70.0 sq mi), it had a population density of 1.6/km (4.1/sq mi) in 2021.

Historical Census Data - Marsoui, Quebec

Year Pop. ±% 1951 621 —     1956 710 +14.3% 1961 724 +2.0% 1966 656 −9.4% 1971 600 −8.5% 1976 541 −9.8% 1981 529 −2.2% 1986 523 −1.1%	Year Pop. ±% 1991 475 −9.2% 1996 440 −7.4% 2001 373 −15.2% 2006 341 −8.6% 2011 309 −9.4% 2016 275 −11.0% 2021 289 +5.1%
Source: Statistics Canada

Canada Census Mother Tongue – Marsoui, Quebec
Census		Total		French				English				French & English				Other
Year		Responses		Count	Trend	Pop %		Count	Trend	Pop %		Count	Trend	Pop %		Count	Trend	Pop %
2021		285		285	5.6%	100.0%		0	0.0%	0.0%		0	0.0%	0.0%		0	100.0%	0.0%
2016		275		270	11.5%	98.2%		0	0.0%	0.0%		0	0.0%	0.0%		5	n/a%	1.8%
2011		310		305	10.3%	98.4%		0	0.0%	0.0%		0	0.0%	0.0%		0	0.0%	0.0%
2006		340		340	8.1%	100.0%		0	0.0%	0.0%		0	0.0%	0.0%		0	0.0%	0.0%
2001		370		370	14.9%	100.0%		0	100.0%	0.0%		0	0.0%	0.0%		0	0.0%	0.0%
1996		445		435	n/a	97.8%		10	n/a	2.2%		0	n/a	0.0%		0	n/a	0.0%

The primary industry of Marsoui is forestry. The Bois Marsoui GDS mill supports 60% of its population. There is also a small tourism industry, including 2 commercial sugar houses. Other businesses provide local commercial and public services.

List of former mayors:

• Alphonse Couturier (1950–1961)
• Oscar Couturier (1961–1971)
• Daniel Goupil (1971–1973)
• Ghislain Deschênes (1973–2001, 2003–2005, 2017–2021)
• Clément Gagné (2001–2003)
• Jovette Gasse (2005–2013)
• Dario Jean (2013–2017)
• Renée Gasse (2021–present)

• List of village municipalities in Quebec

• Official website