The canton of Mormant is a French former administrative division, located in the arrondissement of Melun, in the Seine-et-Marne département (Île-de-France région). It was disbanded following the French canton reorganisation which came into effect in March 2015. It consisted of 22 communes, which joined the canton of Nangis in 2015.

Historical population

Year	Pop.	±%
1999	21,679	—
2006	22,547	+4.0%
2012	23,660	+4.9%

The canton of Mormant was composed of 22 communes:

• Cantons of the Seine-et-Marne department
• Communes of the Seine-et-Marne department

48°36′14″N 2°51′45″E / 48.60389°N 2.86250°E / 48.60389; 2.86250