Austin O'Brien (AOB) is a Catholic high school located in the Ottewell community of southeast Edmonton, Canada. It has about 1000 students.

Austin O'Brien was named after Sir Austin O'Brien, the superintendent of Edmonton Catholic Schools from 1924 to 1961.

Austin O'Brien was opened in 1963 when Edmonton had 18,000 students in the Catholic system and had 55 schools.

The school's Ukrainian-language program began in 1983, and teaches Ukrainian language arts as well as religious studies.

• Johnny Boychuk, New York Islanders (NHL)
• Gene Principe, journalist
• Dustin Cherniawski, CFL football player (Saskatchewan Roughriders)
• Don Davies (1981), Member of Parliament for Vancouver Kingsway, B.C.
• Lydia Dotto, science journalist, author and photographer
• Gordon Hinse, CFL player
• Dexter Janke (Calgary Stampeders)
• Pete Lavorato, Edmonton Eskimos football team (CFL)
• Karrick Martin, curler (multiple Brier appearances)
• Pat McCallum, professional curler (WCT)
• Vikki Moss, singer (left before obtaining diploma)
• Morris Panych, Canadian Playwright
• Terriss Paliwoda, CFL Player
• John Stanton, The Running Room
• Mark Connolly, Broadcaster

• Edmonton Catholic School District