Dicastillo is a town and municipality in the province and autonomous community of Navarre, in northern Spain. It lies within the historic and administrative region of Navarre, which is one of Spain's autonomous communities in the country's north.
The municipality is situated near the towns of Estella and Arellano, which are among its closest neighbours. Estella is the larger of the two and serves as a local reference point for the surrounding area.
As a municipality, Dicastillo covers both the town itself and the surrounding rural territory that falls under its administration. It is one of many small municipalities that make up the Navarre countryside.