Ormesson-sur-Marne (French pronunciation: [ɔʁmɛsɔ̃ syʁ maʁn] ⓘ, literally Ormesson on Marne) is a commune in the southeastern suburbs of Paris, France.

Ormesson-sur-Marne is served by no station of the Paris Métro, RER, or suburban rail network.

The former is located in the neighboring commune of Sucy-en-Brie, 1.8 km (1.1 mi) from the town center of Ormesson-sur-Marne, and the latter is located in the neighboring commune of Saint-Maur-des-Fossés, 1.4 km (0.87 mi) from the town center of Ormesson-sur-Marne.

Schools in the commune include: High school/sixth-form students attend Lycée Samuel de Champlain in Chennevières-sur-Marne.

[7] As of July 2016, Ormesson-sur-Marne is twinned with Northallerton in North Yorkshire.