Castelnuovo is a frazione of the comune of Assisi in the Province of Perugia, Umbria, central Italy.

Castelnuovo is situated about 9 km from Assisi and is located in the southwest of Santa Maria degli Angeli.

Is surrounded also with the territories of other 2 fractions Assisi: Tordandrea to the west, and Rivotorto to the east.

It stands at an elevation of 195 metres above sea level.

[1] The most important watercourse is the river Ose, which basically it specify the frontier between Castelnuovo and Cannara.