Valle Castellana (Ascolano: I Piana) is a village and comune in the Province of Teramo, in the Abruzzo region of central Italy.

It is a member of the Italian community of surrounding mountain villages, Monti della Laga.

The comune takes its name from the Castellana River, which travels north towards Ascoli Piceno in the Marche region.

The comune is bordered by Accumoli, Acquasanta Terme, Amatrice, Arquata del Tronto, Ascoli Piceno, Campli, Civitella del Tronto, Rocca Santa Maria, Torricella Sicura.

The Castellana River basin, along with the Montagna dei Fiori formed the northernmost portion of the Kingdom of Naples.