There are hundreds of Italian cities, here are nine of its most famous:

Rome (Roma) - the capital, both of Italy and, in the past, of the Roman Empire until 285 AD; home of the Roman Catholic Church (the Vatican).
Bologna - home of the first university in the western world. This city is filled with history, culture, and technology. Bologna is well known for its food. One of the world's great university cities.
Florence (Firenze) - the city of Renaissance. This city is known for its architecture and art and for the impact it has had throughout the world. Florence is also home to Michelangelo's famous statue of David. Home to many other well-known museums of art.
Genoa (Genova) - it was one of the most important medieval maritime republic. Very wealthy and diverse city. Its port brings in tourism and trade, along with art and architecture. Genoa is birthplace of Columbus and jeans.
Milan (Milano) - known as one of the main fashion cities of the world, it's also the most important centre of trade and business in all the country.
Naples (Napoli) - is one of the oldest cities of the western world, with a historic city centre that is a UNESCO World Heritage Site. Naples is also near the famous volcano Vesuvius and the ruins of the ancient Roman towns of Pompeii and Ercolano.
Pisa - one the medieval maritime republic, is home to the unmistakable image of the Leaning Tower of Pisa. Very touristy city. Streets are filled with vendors who will try to sell you anything. Famous too for the University "La Normale".
Turin (Torino) - first capital of Italy, after being the capital of Kingdom of Sardinia (actually Piedmont-centred), what had promoted national reunification. Home of the FIAT, the most important industry in Italy,. Turin is a well known industrial city, based on the aerospace industry and, of course, automobile industry. Home of the 2006 Winter Olympics.
Venice (Venezia) - known for its history (the most important, beside Genoa and Pisa, of the medieval maritime republics), art, and world famous canals. One of the most beautiful cities in Italy; it is home to Island of Murano, which is famous for its hand-blown glass. St. Mark's Square is where most of the tourists are and can get very crowded in the summertime.