South Pasadena High School (SPHS or "South Pas") is the one public high school serving grades 9–12 in the city of South Pasadena, California. With the South Pasadena Middle School and three elementary schools (Arroyo Vista, Marengo, and Monterey Hills) it makes up the South Pasadena Unified School District.

Established in 1905, it is the only public high school in South Pasadena. The campus is on the west side of the city on Fremont Avenue. The school contains several main academic buildings, a performing arts auditorium, a swimming pool, two sets of tennis courts, two indoor gymnasiums, a 400-m outdoor track, and three athletic fields. The school's motto is "Scholarship, Leadership, Strength, and Fair Play." The school colors are orange and black, and the mascot is a tiger.

SPHS opened in 1906 after South Pasadena city officials approved a measure to construct a public high school in 1904. Until 1955, South Pasadena High School was known as South Pasadena-San Marino High School and served both cities. In 1954, the city of San Marino chose to withdraw from SPHS and to established San Marino Unified School District, along with San Marino High School

The school offers a variety of sports such as baseball, volleyball, football, water polo, basketball, cross country, soccer, track and field, tennis, and others. Additionally, the school also has a marching band, which has won numerous titles in the Western Band Association (WBA) circuit. A new athletic director, Anthony Chan, was hired in 2019.

The football field at South Pasadena High School is known today as Ray Solari Stadium in honor of the former football head coach, where South Pasadena High's football team plays their home games. It is also used for boys and girls' soccer teams and for track and field meets as well as for graduation ceremonies.

The school was one of the first to work with the Children's Hospital Los Angeles and the mobile Sports Analysis Lab, to help demonstrate how data is collected, evaluated, and assessed to study athletes biomechanics.

In 2019 the school was recognized due to its U.S. News & World Report ranking. It was ranked #1 in California's 41st State Assembly District, #87 in the state and #622 out of 17,000 public high schools within the United States, placing in the top 5% of schools nationwide. It was also ranked #675 out of 5,000 by Newsweek for the top STEM high schools of 2019.

• Steven Alvarez – actor/business entrepreneur
• William Bradford Bishop – Former United States Foreign Service officer, accused murderer and wanted fugitive
• Alison Brie – actress
• John Bush – Professional Musician, Singer for the band Armored Saint
• Wesley Chesbro - California Assemblyman and Senator
• John Gabbert – Associate Justice of the California Court of Appeals
• Bobby Garrett – former NFL player
• Mike Giddings - college football coach, NFL scout
• John Hart – actor
• George Hodel – physician accused of 1947 murder of Elizabeth Short, a.k.a. the Black Dahlia, and of committing several additional murders
• William Holden - (William Beedle) – actor
• Tommy Hutton - former Major League Baseball player
• Porochista Khakpour - novelist, writer and reviewer for national and international publications
• Bob Long – former NFL player
• Mary Bono Mack – U.S. Congresswoman
• Gordon S. Marshall - Businessman, namesake of USC's Marshall School of Business
• Pete McClosky - U.S. Congressman
• Adrian Picardi – director
• Bronson Pinchot – actor
• Ward Ritchie – master printer, book designer
• John H. Rousselot - U.S. Congressman
• Noelle Scaggs – singer (Fitz and the Tantrums)
• Shanice – singer
• Leslie Smith - fighter
• Hilary Swank – actress
• Jaleel White – actor
• Kristinia DeBarge – singer
• Chris Spencer – actor/director/comedian

• South Pasadena High School
• Historical South Pasadena High School Yearbooks

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