Gresham’s School is an independent coeducational boarding school in Holt in Norfolk, England.The school was founded in 1555 by Sir John Gresham, who converted Holt’s Manor House into a Free Grammar School as a result of Henry VIII’s suppression of the Monasteries. 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. It survived the Great Fire of 1708 which destroyed most of medieval Holt and was extensively enlarged and refurbished in Victorian times. Renamed ‘Old School House’ it currently serves as home to the Pre-Prep School. 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 under the direction of a new and innovative headmaster, George Howson 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. The Senior School and Prep School are presently located along both sides of Cromer Road on the eastern edge of Holt.

Gresham's began to admit girls in the early 1970s 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 original senior school. Altogether, the three schools teach about eight hundred children. There are four boarding houses for boys and three for girls and a wide range of buildings which include Big School, the School Chapel, the Auden Theatre, the Cairns Centre, the School Library, the Music Centre, the Central Block, the Thatched Classrooms, the Reith Laboratories, the Biology Building, the Armoury, and others. Gresham's School is one of the top 30 International Baccalaureate schools in England.

Benjamin Britten, Lord Britten of Aldeburgh, was a Gresham's OB.