Saint-Malachie (French pronunciation: [sɛ̃ malaʃi]) is a village located in the Bellechasse Regional County Municipality, part of the Chaudière-Appalaches administrative region. The Etchemin River runs through the municipality.

Saint-Malachie was colonized by the Irish and Scottish shortly after the War of 1812. The land was given to several British soldiers in the eastern part of the township of Frampton along the Etchemin River.

The land was then granted to Gilbert Henderson (1785–1876), who later became the major landowner in the area. The first settlers came mainly from the county town of Armagh, in Northern Ireland. The town was named after Saint Malachy, the archbishop of Armagh. The town was civilly erected in 1874 and would later give its name to the municipality of Saint-Malachie-de-Frampton (Frampton Township) before adopting its current name in 1948.

The toad invasion of 1873 was quite significant for the town and is embedded in its culture and history to this day. La Crapaudière, the mountain named after the toad invasion (from the French crapaud), once an operating ski hill, is now a special tourist attraction where people gather to hike and enjoy the scenery.

The original village cemetery was the first Catholic cemetery in the upper Châteauguay Valley and dates back to the late 1820s. There was not an official parish at that time, but the cemetery served all residents of Saint-Malachie and the surrounding areas. The site is now privately owned farmland, and its monuments have been dispersed locally. In the 1960s, the local parish arranged to establish a commemorative memorial on the side of the road where it was originally located.

Henderson Manor, a historical landmark, is located along the Etchemin River at the south end of the village.

The colour yellow represents Saint-Malachie's dominant industry, agriculture; namely, the farming of poultry, dairy, beef, and pork products. The two croziers symbolize the municipality's namesake, Saint Malachy, a 12th-century Archbishop of Armagh. The toad, centered, calls back to the great infestation of 1873. Three white-tailed deer, which are omnipresent in the municipality's landscape, stand on a grassy mound set with lilies, roses, shamrocks, and thistles, wearing coronets adorned with maple leaves and fir cones. The thistles are a nod to the region's early Scottish landowners, while the shamrocks represent the Irish migrants who settled there in the 19th century, whose legacy has left a lasting imprint on the local culture.

St. Malachie is surrounded by Tough Creek and the South Etchemin River, among other bodies of water and lakes. In season, it is a great spot to go hunting and go fishing, most notably for speckled trout.

St. Malachie is also home to Mont Kinsella, a mountain peak which provides a panoramic view of the town. It is ranked as the 871st highest mountain in Quebec.

The Committee footpath is a scenic trail throughout St. Malachie measuring 27.3 kilometers long. It runs along the forest areas and it is equipped with resting areas in places where nature can be easily admired. The footpath is also equipped with stairs and panels which indicate the species and natural vegetation you may see along the path. The footpath is closed during the winter season and reopened in the spring.

Saint-Malachie follows the four distinct seasons of spring, summer, winter and fall and it is located in the northeastern tip of North America.

It follows three types of climate throughout the seasons: humid, subarctic and arctic. Daily sunshine duration is eight hours in December, the time of year when it is the shortest.

In the 2021 Census of Population conducted by Statistics Canada, Saint-Malachie had a population of 1,667 living in 699 of its 812 total private dwellings, a change of 9.9% from its 2016 population of 1,517. With a land area of 101.07 km (39.02 sq mi), it had a population density of 16.5/km (42.7/sq mi) in 2021.

In 2009, the non-profit Portage rehabilitation center for youth dealing with substance abuse issues was established in Saint-Malachie. The French-language residential program caters to adolescents and young adults aged 14 to 21.

Saint-Malachie has multiple organizations that cater to a large spectrum of people. These include:

• Circle Farming St. Malachie: dedicated to improving lives of women and families through craft heritage
• Knights of Columbus
• Hunting and Fishing Club Inc.
• Couples Escorts South Shore Regional: service preparation for Christian marriage
• St. Patrick's Society: organize celebrations for St. Patrick's day and to preserve Irish heritage
• Coupling St. Malachie Club: gathering people interested in horse breeding and promoting the use of horses in leisure
• Club FADOQ St. Malachie: entertain, inform and enhance the participation of seniors, building a Quebec for all generations.

• Major Joseph Phydime Lionel Gosselin (1911–1951), veteran of World War II and the Korean War
• Miville Couture (1916–1968), actor and radio host with Radio-Canada
• Francis O'Farrell (1919–1992), member of the National Assembly for the Liberal Party from 1964 to 1966 in Dorchester
• Paul-Henri Picard (1923–2002), member of the National Assembly for the Union nationale from 1966 to 1970 in Dorchester