St Leo's Catholic College is a Catholic systemic secondary day school for boys and girls, located in the Upper North Shore suburb of Wahroonga in Sydney, New South Wales, Australia. Situated in the Diocese of Broken Bay, the high school currently has approximately 800 students from Year 7 to Year 12.

Wahroonga is a suburb in the Upper North Shore of Sydney, in the state of New South Wales, Australia, 18 kilometres north-west of the Sydney central business district, in the local government areas of Ku-ring-gai Council and Hornsby Shire. North Wahroonga is an adjacent separate suburb of the same postcode.