Guelph has several meanings:

• Guelph is a city in Ontario, Canada.
• University of Guelph.
• The House of Guelph is a noble family, more commonly known as the House of Welf.
• The Guelphs and Ghibellines were factions supporting, respectively, the Papacy and the Holy Roman Empire in Italy during the 12th century and 13th century.