Gresham's School is a public school (English independent day and boarding school) in Holt, Norfolk, England, one of the top thirty International Baccalaureate schools in England.The school was founded in 1555 by Sir John Gresham as a free grammar school for forty boys, following King Henry VIII's dissolution of the Augustinian priory at Beeston Regis. The founder left the school's endowments in the hands of the Worshipful Company of Fishmongers of the City of London, who are still the school's trustees.

In the 1890s, an increase in the rental income of property in the City of London led to a major expansion of the school, which built many new buildings on land it owned on the eastern edge of Holt, including several new boarding houses as well as new teaching buildings, library and chapel.

Gresham's began to admit girls in 1971 and is now fully co-educational. As well as its senior school, it operates a preparatory and a nursery and pre-prep school, the latter now in the Old School House, the historic home of the school. Altogether, the three schools teach about eight hundred children.