Paul Roos Gymnasium is a leading public dual medium (Afrikaans & English) high school for boys in the town of Stellenbosch in the Western Cape province of South Africa, which opened on 1 March 1866 as Stellenbosch Gymnasium.

A notable characteristic of the school is its gees (Afrikaans for spirit) and their famous fight song "Old boys of Paul Roos" which has the melody of "Flower of Scotland" in remembrance of the first three Scottish rectors, which they sing with their old boys.

It is also the school with the most players in the 2019 Rugby World Cup including five Springboks: Schalk Brits, Willie le Roux, Steven Kitshoff, Herschel Jantjies, Damian Willemse and Braam Steyn who played for Italy.

The school is dual medium;[5] Afrikaans- and English-speaking pupils study under one roof, but classes are largely separated according to mother tongue.

Paul Roos Gymnasium is one of four schools in South Africa entitled to award a Rhodes Scholarship annually to an ex-pupil to study at the University of Oxford.