St George's School, Harpenden is a non-selective day and boarding school in Harpenden, Hertfordshire, England, educating students of both sexes between the ages of eleven and eighteen, with an emphasis on its Christian ethos. It was founded in 1907 as one of Britain's first mixed-sex boarding schools. The school has International School status. The School was named as the Sunday Times' 'Comprehensive School of the Year' in 2019. In 2022, the School was ranked as the 122nd best secondary state school in the country based on combined GCSE attainment and A-Level point scores.

Harpenden is a town and civil parish in the City and District of St Albans in the county of Hertfordshire, England. The population of the built-up area was 30,674 in the 2021 census, while the population of the civil parish was 31,128. Harpenden is a commuter town, with a direct rail connection to Central London.