Viroflay (French pronunciation: [viʁɔflɛ] ⓘ) is a commune in the Yvelines department in the Île-de-France in north-central France.

The town motto is Lux mea lex which is Latin for "Light is my law".

The "Monstruous" is a variety of spinach, specific to Viroflay where it used to be cultivated.

Viroflay is served by Viroflay-Rive-Gauche station, which is an interchange station on Paris RER line C and on the Transilien Paris-Montparnasse suburban rail line.

It is also served by Viroflay-Rive-Droite station on the Transilien Paris-Saint-Lazare suburban rail line and by Chaville–Vélizy station on Paris RER line C.