San Donato is a village in Tuscany, central Italy, administratively a frazione of the comune of Orbetello, province of Grosseto, in the Tuscan Maremma.
At the time of the 2011 census its population amounted to 18.
The village was founded in the late 1950s as a result of the riforma fondiaria (land reform) in Maremma.
It is divided into the hamlets of San Donato Centro and San Donato Vecchio.
It is known for the Sagra della Panzanella, a festival held every summer since 1999 to celebrate the Tuscan dish panzanella.