A Crown Prince or Crown Princess is the heir or heiress apparent to the throne in a royal or imperial monarchy. (Crown Princess is also the title of the wife of the Crown Prince.) In Europe, lineal succession conventions (see for example Salic Law) usually dictate that the eldest child (as in Sweden, Belgium, Norway and the Netherlands) or the eldest son of the current monarch (United Kingdom, Spain, Denmark etc) fills this role, but in Arab monarchies, for example, succession rules may differ and a Crown Prince may gain the title on merit, or because someone is not seen as a threat to the reign of the current monarch; in such cases a person granted the title may also lose it, with it being granted to another member of the Royal Family.

Compare heir apparent and heir presumptive.

It should however be noted that, although it is often used as a generic term for heir apparent, it is seldom an official title in the European monarchies. Currently, only the heirs apparent to the Scandinavian monarchies officially bear the title, while the heir presumptive normally would be titled Hereditary Prince. Many monarchies use special titles

• Blessed Prince (al-Amir as-Sa'id) (Egypt and Sudan)
• Dauphin (France)
• Prince of the Asturias (Castile, Spain)
• Prince of Gerona (Aragon, Spain)
• Prince of Viana (Kingdom of Navarre)
• Duke of Braganza, Prince of Beira and/or Prince of Brazil (titles of the Portuguese heir after 1640)
• Prince of Orange (House of Orange-Nassau) (The Netherlands)
• Duke of Brabant (Belgium)
• Duke of Calabria (Kingdom of the Two Sicilies)
• Prince Imperial (Napoleonic France)
• Tsesarevich (Russia)
• Prestolonaslednik (Serbia)
• Duke of Cornwall (England, Great Britain, United Kingdom)
• Duke of Rothesay (Scotland, Great Britain, United Kingdom)
• Prince of Wales (England, Great Britain, United Kingdom)
• HuangTaizi (皇太子) (Imperial China)
• Kōtaishi (皇太子) (Japan), if a son; Japan also has a title kōtaison (皇太孫) if the heir is a grandson

See also: Crown Prince Party of the People's Republic of China