Gregorio Pagani (3 December 1558 – 1605) was an Italian painter of the late Mannerist period, active mainly in Florence. He was the son of the painter Francesco Pagani, then became a pupil of Santi di Tito, then entered the studio of Ludovico Cigoli. He painted the St. Helena finding the Cross for Santa Maria del Carmine, which was lost in the fire at the church in 1771. He painted a Nativity for the cathedral of Santa Maria del Fiore. Among his pupils were Cristofano Allori and Matteo Rosselli.