The official patron saint of the city is Saint Geminian of Modena (Geminiano), who is a saint of the Catholic Church.

However, the city still honors St. Fina (Seraphina), who was born in San Gimignano and died there on 12th March 1253. The collegiate church houses the Santa Fina Chapel, which is a shrine to the saint, which is decorated with frescoes by Domenico Ghirlandaio.

A house still stands in San Gimignano and is said to be the home of Saint Fina.