Sainte-Justine (French pronunciation: [sɛ̃t ʒystin]) is a municipality in the Les Etchemins Regional County Municipality in Quebec, Canada.

It is part of the Chaudière-Appalaches region and the population is 1,835 as of 2009.

It is named after Marie-Justine Têtu, wife to Hector-Louis Langevin, member of Parliament for Dorchester.

It is home to a regional secondary school, Polyvalente des Appalaches.

The famous Canadian short story The Hockey Sweater takes place in Sainte-Justine, the hometown of the author, Roch Carrier.