Some of Saint Mary's notable alumni are as follows:

• Joseph Alioto '37, (dec.) former mayor of San Francisco
• Brother Mel Anderson '51, president, Saint Mary's College for 27 years
• Brother Alfred Brousseau '28 (dec.) mathematician, widely-renowned authority on the Fibonacci numbers
• Laura (Garcia) Cannon '91, anchorwoman, NBC-11
• Jackson Graves '1872, (dec.) first graduate, Los Angeles historian
• Shirley Griffin '93, Executive Vice President, Wells Fargo Bank
• James Guyette '67, President & CEO, Rolls-Royce of North America, Inc.
• Robert Hass '63, Poet Laureate of the United States, 1995-97
• Jack Henning '38, former U.S. Ambassador to New Zealand; California labor leader
• Ken Hofmann '45, owner, Oakland Athletics; developer
• Harry Hooper '07, (dec.) National Baseball Hall of Fame
• John Henry Johnson '53, Pro Football Hall of Fame
• Bob Ladouceur '89, head football coach, De La Salle High (Concord), holder of longest high school winning streak
• Herman Lujan '58, provost, Cal State University, Los Angeles
• Manuel Lujan '50, former Secretary of the Interior, 1989-1993; Congressman (NM), 1969-1989
• Tom Lyons '50, activist, Catholic Relief Services; detention minister
• Ronald McArthur '49, founder, St. Thomas Aquinas College
• John Macken '62 scientist, inventor with numerous patents. Developed LaserCraft technology
• Tony Martin '35, entertainer; member, Hollywood Walk of Fame
• Brother Leo Meehan '08 (dec.), famed academian; author; orator
• Tom Meschery '61, pro and college basketball great; teacher and poet
• George P. Miller '12 (dec.), Member of Congress from California, 1945-1973
• Nicholas Moore '63, Chairman (Retired), PriceWaterhouseCoopers
• Don Perata '67, Majority Leader & Senator, California State, 1998-
• Dr. Andrea Pernell-Sawicki '83, Surgeon; member, SMC Athletics Hall of Fame
• Quentin Reynolds '29 (dec.), former Chairman, CEO, Safeway Stores, Inc.
• George Schmitt '65, President (Retired), Omnipoint Communication & AirTouch International
• Raymond Syufy, Sr. '40 (dec.), Founder, Century Theaters
• Mark Teahen '03, major league baseball player; SMC career batting average record holder (.386); former all-WCC player; drafted by the Oakland Athletics and featured in the bestselling Michael Lewis book Moneyball; currently with the Chicago White Sox.
• Brother Jerome West '40 (dec.), Christian Brothers Provincial; founder of 3 high schools
• Herman Wedemeyer '49 (dec.), football star; Hawaii legislator; original cast of "Hawaii 5-0"
• Dr. Carl Wu '74, distinguished cancer researcher, National Institute of Health