The Prince-Bishopric of Hildesheim was an ecclesiastical principality of the Holy Roman Empire from the Middle Ages until its dissolution in 1803. The Prince-Bishopric must not be confused with the Diocese of Hildesheim, which was larger and over which the prince-bishop exercised only the spiritual authority of an ordinary bishop.

In the Holy Roman Empire, the German term Hochstift referred to the territory ruled by a bishop as a prince, as opposed to his diocese, generally much larger and over which he exercised only spiritual authority. The terms prince-bishopric and ecclesiastical principality are synonymous with Hochstift. Erzstift and Kurerzstift referred respectively to the territory (prince-archbishopric) ruled by a prince-archbishop and an elector-archbishop while Stift referred to the territory ruled by an imperial abbot or abbess, or a princely abbot or abbess. Stift was also often used to refer to any type of ecclesiastical principality.