It dates back to the fourteenth century and is the larger of two non-comprehensive gymnasia in Groningen, the other being Willem Lodewijk Gymnasium.
Fourteenth century records show that an early predecessor of the Praedinius Gymnasium, the Schole tho Sunte Meerten, was situated at the current location of the Provinciehuis (Province Hall).
Fourteen years later, the school moved to a new building, at the location of the current Harmonie.
On 1 September 1882, the school moved for the last time, to a new building at the Turfsingel.
In 1999, due to a lack of space, a second building, the old industrial school, was added to the Praedinius.