Castelbellino is a comune, or municipality, situated in the Marche region of central Italy. It is located within the Province of Ancona and is positioned approximately 35 kilometres (22 miles) southwest of the city of Ancona.
As a local administrative division, Castelbellino serves as a constituent part of the regional infrastructure in the Marche territory. The municipality is defined by its geographic proximity to the provincial capital and its placement within the Italian peninsula.