Italian painter and architect who led the formation of the Cremonese school. His work, and that of his followers, was elegant and eclectic. Campi was a prolific painter, working in both oil and fresco; at its best his work was distinguished by the richness of its colour.

He first studied under his father, Galeazzo (1477–1563). Among the earliest of his school were his brothers, Vincenzo (1536–91) and Antonio (1536–c. 1591); the latter was also a sculptor and historian of Cremona. Bernardino Campi (1522–c. 1592), unrelated to the family, was a pupil of Giulio and master of Elena and Sofonisba Anguissola.