Castelnuovo Don Bosco is a comune (municipality) situated in the Piedmont region of northern Italy. It is located within the province of Asti, positioned approximately 20 kilometres east of Turin and about 25 kilometres northwest of Asti.
The town was formerly known as Castelnuovo d'Asti. Geographically, it sits on a hill near the confluence of the Nevissano and Bardella rivers.