Saint Ignatius' College, Adelaide, is an independent co-educational day school located in Adelaide, South Australia, part of the international network of Jesuit schools, which began in Messina, Sicily, in 1548. The patron saint of the College is the founder of the Society of Jesus (the Jesuits), Ignatius of Loyola. The College has two campuses: the Junior Campus in Norwood, containing the Junior School (Reception to Year 6 students) and Early Childhood Centre (3 to 5 years old), and the Senior Campus in Athelstan, located across some 16 hectares of land, home to the Senior School (Year 7 to 12 students).

The College began in Queen Street, Norwood, South Australia, commencing with fifty-two boys and six Jesuit fathers on 13 February 1951. The catalyst was Archbishop Matthew Beovich's increasing interest in commencing more formalized Catholic schooling in Adelaide. Thus, the Jesuit boys' day school was established. The initial intake was from Grade 3 onwards. Students prior to this year level were educated at Loreto College, St Joseph's Memorial School (the local parish school), or the local state schools.

The school grew quickly and in 1967, a secondary campus was opened at Athelstan, in the then outer suburbs of Adelaide, South Australia and the Norwood campus became the Junior School. From 1971, the school accepted Kildare College enrolments from girls wanting to complete their secondary studies. At that stage, Kildare offered education up to Year 11. In 1996, the school changed to offer co-educational enrolments from Reception to Year 12, the first Jesuit school in the world to do so. A co-educational Reception to Year 12 College.

In 2005, the College and Mercedes College hosted their inaugural 'Intercollegiate Sports Carnival' ('Intercol'). Each year the senior students of both colleges participate in eight sports for twenty-one shields in the winter season. The school that wins the majority of the shields is the overall winner of the Carnival and of the 'Mercedes-Ignatius' Shield. Each school alternates the hosting of Intercol each year. A significant celebration and event in the College community is the annual Patronal Feast Day of Saint Ignatius. A school mass is held at the Norwood Parish for current students and staff of the school; it is one of only two events in the College calendar where students from both campuses are gathered in one place. Saint Ignatius' feast day is celebrated on 31 July.