In his youth Tajani was a militant of Fronte Monarchico Giovanile (Youth Monarchist Front), a student organization of the Monarchist party of Italy. Even later, he has always advocated for the return from exile of the House of Savoy (banned according to the Italian Constitution until 2002, when the Italian Parliament lifted the ban).

He was one of the founders of the nationalist and populist Forza Italia party in 1994, then regional coordinator of the party in Lazio from 1994 in 2005.

In the first Berlusconi’s government (1994–95), Tajani was a spokesman of the Prime Minister.