Guillaume Gazet, Latinized Gulielmus Gazaeus (1554–1612) was a poet and ecclesiastical historian in the Spanish Netherlands.
His brother, Antoine Gazet, was a physician and translator.
Gazet was born in Arras, then part of the Habsburg Netherlands (now in France), in 1554.
Around 1580 he was appointed parish priest of the church of Sainte-Marie-Madeleine in Arras, and later became a canon of the collegiate church of Saint-Pierre in Aire-sur-la-Lys while retaining his position as parish priest.
He died in Arras on 25 August 1612 and was buried in his parish church there.