Joncas may refer to:
People Grace Joncas (1923–2024), American politician Jean-Luc Joncas (born 1936), businessman and politician Louis-Zéphirin Joncas (1846-1903), Canadian politician Maurice Joncas (1936-2021), Canadian writer Maxime Blanchette-Joncas (born 1989), Canadian politician Michael Joncas (born 1951), Catholic priest
Other Joncas River, a disambiguation page