He holds a law degree. Marzano is an economist. He worked at Abruzzi University from 1968 to 1971.
He has been professor of economic and financial politics at the University of Rome since 1974 and professor of economic policy at the Libera Università Internazionale degli Studi Sociali university of Rome since 1978.
He was the economic advisor to Silvio Berlusconi in the 1990s. He served as president of the International Association of Economic and Social Councils and Similar Institutions (AICESIS) and is currently its honorary president
He was appointed minister of productive activities to the cabinet of Prime Minister Berlusconi in 2001. Claudio Scajola replaced him in the post on 23 April 2005.
His tenure in the parliament ended in 2005.
On 22 July 2005 he was appointed president of the CNEL.
He is a member of the Forza Italy. In 1996, he became a member of the Italian Parliament. He is a member of the Italy-United States of America Foundation.
Then Marzano became a member of the CNEL (National Council for Economics and Labour).