Mattiolo, born in Rome on October 28, 1957, graduated in Political Science at the University of Rome “La Sapienza” in 1980. The following year he embarked on a diplomatic career that led him to the Directorate General for Emigration and Social Affairs, where he worked for two years until 1983.
He then undertook his first foreign mission as Second Secretary to the Italian Embassy in Moscow, then the Soviet Union. He held this position until 1986, when he was appointed First Secretary at the Italian Embassy in Bern, Switzerland. In 1988 he was appointed First Secretary at the Italian Embassy in Belgrade, where in May 1991 he was appointed Legation Counsellor.
Is sent overseas for the first time to New York as Permanent Representation Advisor to the UN. In 2004, after his appointment as Minister Plenipotentiary, he returned to the Ministry of Foreign Affairs, in the Directorate General for European Integration, with the task of European Correspondent and Coordinator of the activities related to the Common Foreign and Security Policy.
In 2005 he was appointed Minister to the Permanent Representation to the Atlantic Council in Brussels, a position he held until 2008. In September of that year he was appointed Ambassador of Italy to Tel Aviv where he remained until 2012, when he returned to the Foreign Ministry as Director General for the European Union. In 2013 he was promoted to the rank of Ambassador.
He then served as Ambassador of Italy to Turkey in Ankara between March 2015 and November 2018. He was appointed Ambassador to the Federal Republic of Germany in Berlin.