The Federation of Italian Socialists (Federazione dei Socialisti Italiani, FSI) was a social-democratic political party in Italy.
In January 1994 the Italian Socialist Party (PSI), severely hit by the Tangentopoli scandals, was in disarray. The new party secretary, Ottaviano Del Turco, led the party into the Alliance of Progressives, a left-wing coalition dominated by the post-communist Democratic Party of the Left (PDS), but a group of dissidents disagreed. On 28 January they left the PSI and formed the FSI. The new party included Franco Piro (secretary), Margherita Boniver (president), Ugo Intini and Maurizio Sacconi.
In the 1994 general election the FSI formed a joint list with the Italian Democratic Socialist Party (PSDI), led by Enrico Ferri, and some independents, notably including Dacia Valent. The list obtained a mere 0.5% of the vote. In 1996 he FSI was merged into the Socialist Party (PS). Many leading members of the FSI (Boniver, Sacconi, etc.) later entered Silvio Berlusconi's Forza Italia, while others (Piro, Intini, etc.) were founding members of the New Italian Socialist Party (NPSI) in 2001.