Pailhès (French pronunciation: [pajɛs]; Occitan: Palhèrs) is a commune located in the department of Ariège in Midi-Pyrenees in southwestern France.

This commune is located in the mountains of Plantaurel on the river Lèze and on the old national road 628 between Saint-Jean-de-Verges and Campagne-sur-Arize.

As such it was of military significance in the Middle Ages, which resulted in the Chateau of Pailhes being built on the hill overlooking the river.

The chateau was built in the 12th century by the Comte de Foix and reached a high point when King Henri II of France stayed the night there.

Unfortunately this unique railway line was torn up in the inter-war years, though the stations can still be seen in each of the villages of the Lèze.