Bruno Valentini (born 29 May 1955 in Colle di Val d'Elsa) is an Italian politician.Valentini started his political career in Siena and then as a municipal councillor in Monteriggioni, Tuscany, in 1995.
He served as Mayor of Monteriggioni from 2004 to 2013.
He has been a member of the Democratic Party since 2007.Valentini was elected Mayor of Siena on 11 June 2013.
He ran for a second term at the 2018 Italian local elections, but was defeated by the centre-right candidate Luigi De Mossi.