The canton Longjumeau has 8 communes.
| Code | Name | Population ▼ |
|---|---|---|
| 91345 | Longjumeau | 21 996 |
| 91216 | Épinay-sur-Orge | 10 722 |
| 91425 | Montlhéry | 9 772 |
| 91665 | La Ville-du-Bois | 8 161 |
| 91339 | Linas | 7 987 |
| 91587 | Saulx-les-Chartreux | 6 733 |
| 91044 | Ballainvilliers | 4 904 |
| 91136 | Champlan | 2 615 |