Ristigouche-Sud-Est (French pronunciation: [ʁistiɡuʃ syd ɛst]; or Ristigouche-Partie-Sud-Est until February 2024) is a municipality in Quebec, Canada, near the head of the Baie de Chaleur.

It is a rural municipality without population centres, situated along the CN Railway line which hosts the VIA Rail Ocean (train) route; the nearest VIA station is Matapedia.

Construction started in 1830, under the supervision of William MacDonald, Frederic Fournier and Major Wolfe, but the route remained difficult and government decided to abandon it in 1857.

A new path between Causapscal and the Restigouche was adopted in 1862, and in 1868 the Intercolonial Railway project that was to transform the British North American Colonies into Canada selected the Matapedia River road to be its route.

[4] now a subsidiary of the French multinational oil producer Maurel et Prom [fr],[5] The municipality had amassed $146,000 in its charitable legal defence fund as of March 2015.