During the festival, state-of-art Italian industry and designer achievements will be shown in the city's Mimara Museum until 4 June.
Simultaneously, the festival is taking place in 20 other countries on the occasion of the 60th anniversary of the establishment of the Italian Republic which is celebrated on 2 June.
Croatian Deputy Prime Minister Damir Polancec said at the opening of the Zagreb festival that trade between Croatia and Italy reached 4.7 billion euros in 2005.
Italians have invested more than 800 million euros in Croatia since the country gained independence.
Italian Ambassador Alessandro Grafini said those figures were conservative, and explained that according to his statistics Italian investments exceeded one billion euros, while bilateral trade came to five billion euros annually.
Grafini added that last year, 1.2 million Italians were on holiday in Croatia.
The festival was organised by the Italian Embassy in Zagreb, the Italian Institute for Foreign Trade, the Italian Culture Institute and the advisory board of Italian entrepreneurs operating in Croatia.