The first classes commenced in 1956, with 118 students in Year 3 to Year 6. The College was named after St Leo the Great, who was one of the early Popes of the Catholic Church. St Leo famously went forth from Rome, with the cross as his standard and defence to plead with Attila the Hun to spare the eternal city and its people. By the force of his personality, he succeeded where others had failed. After he died in 461 AD, St Leo was honoured for his work with the title of Doctor of the Church.

The year 1983 was a momentous one in the College’s history. By 1983, the Brothers  were unable to staff the College and so its administration was passed to the Catholic Education Office, Sydney. Upon the departure of the Christian Brothers, the first lay Headmaster was appointed. The College became co‑educational, with the first girls enrolling in Year 11 in 1983 and Year 7 in 1984. By 1987 the College completed the integration of co-education at the College. When the newly created Diocese of Broken Bay was formed, the College came under the jurisdiction of the Catholic Schools Office, Broken Bay.

In the 1980’s the College undertook an extensive building program including the creation of the Brother Crohan Library and the Brother Berg Building, incorporating a multi-purpose hall and extensive art and hospitality facilities. In 2002 a new Technology Centre was constructed placing St Leo’s at the forefront of technological learning. The Light of Christ Centre was opened in 2012, providing high quality sporting facilities for the College. The College is currently undergoing an extensive building works program which will see new 21st Century learning facilities for all students, including new Science Laboratories, new learning areas, renovation of the historic College chapel, new outdoor recreation spaces, a new Hospitality Hub, upgraded TAS facilities and a new Creative and Performing Arts Centre.

The current St Leo’s community is indebted to the Christian Brothers for the strong Catholic foundation that was established for the College. At present the College has over 800 students from Years 7–12. As a Catholic, comprehensive, co-educational high school, the College exists to provide the best possible faith, learning and growth environment for the College community. The College strives to provide a holistic Catholic education designed to assist each student to achieve their own personal best.


  • “We chose this high school for our children because of the pastoral care for the students and the academic focus that is balanced with physical development.”

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16 Woolcott Ave Wahroonga
NSW 2076
Phone: 02 9487 3555
Fax: 02 9487 2637

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