Simone Martini (c. 1284 – 1344) is an Italian painter born in Siena.

He is a major figure in the development of early Italian painting and greatly influences the development of the International Gothic style.

It is thought that Martini was a pupil of Duccio di Buoninsegna, the leading Sienese painter of his time.

Giorgio Vasari states Simone was a pupil of Giotto di Bondone the most famous painter from Florence with whom he went to Rome to paint at old St. Peter's Basilica, Giotto also executing a mosaic there.

Simones brother-in-law is the artist Lippo Memmi.

Very little documentation survives regarding Simone's life, and many attributions are debated by art historians.

Simone Simone Martini dies while in the service of the Papal court at Avignon in 1344.