Giovanni Battista Giustammiani, also called il Francesino (active 1608 to 1643) was an Italian painter active mainly painting sacred subjects in a late-Mannerist style in Siena, Tuscany, Italy.
Giustammiani's works primarily depict religious scenes and figures.
He painted the Miracles of Benedictine Saints for the sacristy of San Domenico.
For the church of San Raimondo, he created an altarpiece depicting the Circumcision of Jesus.
[1] Another notable work by Giustammiani is a depiction of Saint Dominic in Soriano originally painted for the Propositura di Santa Croce [it] in Greve in Chianti, Tuscany.