St. Augustine Catholic High School is a Separate high school in Markham, Ontario, Canada. It is a technologically oriented school, is part of the York Catholic District School Board, and opened in 2001. As of September 2019, it had an enrolment of 1082 students and 80 faculty members. In the Fraser Institute's Report Card on Ontario’s Secondary Schools 2019, the school was ranked 12th out of 739 secondary schools in Ontario with an overall rating of 8.8 out of 10.

The York Catholic District School Board is the English-language public-separate school district authority for the Regional Municipality of York in Ontario, Canada. Its head office is in Aurora.