Castelnau-le-Lez (French pronunciation: [kastɛlno lə lɛz] ⓘ; Occitan: Castèlnòu de Les) is a commune in the Hérault department in the Occitanie region of Southern France.

Located on the outskirts of Montpellier, it is situated around 3 km (1.8 mi) north of the city centre.

Hundreds of Jewish children were hidden in the town of Castelnau-le-Lez during the Holocaust.

Almost every home hid children, in some cases from multiple families.

The people of the town and the local priest were well aware of the situation and, at least tacitly, supported it.