The canton of Boulogne-sur-Mer-Sud is a former canton situated in the department of the Pas-de-Calais and in the Nord-Pas-de-Calais region of northern France. It was disbanded following the French canton reorganisation which came into effect in March 2015. It had a total of 22,763 inhabitants (2012, without double counting).

The canton is organised around Boulogne-sur-Mer in the arrondissement of Boulogne-sur-Mer. The altitude varies from 0m (Boulogne-sur-Mer) to 188m (Saint-Martin-Boulogne) for an average altitude of 46m.

The canton comprised 5 communes:

• Baincthun
• Boulogne-sur-Mer (partly)
• Echinghen
• Saint-Martin-Boulogne
• La Capelle-lès-Boulogne

• Cantons of Pas-de-Calais
• Communes of Pas-de-Calais
• Arrondissements of the Pas-de-Calais department

50°43′10″N 1°39′28″E / 50.71944°N 1.65778°E / 50.71944; 1.65778