You can get to Rome from this airport:
By Special Train Leonardo Express: train leaves every day from Fiumicino Airport station every 30 minutes (from 6:37 to 23:37) and it stops at the Rome Termini Railway Station without no mid-journey stops. Ticket costs around € 14,00.
By Taxi: taxis are available at the arrivals areas of the terminals. The aproximative fare for a run to the center of Rome is about € 50,00. Supplements might be asked for luggage, night-time runs and public holidays. It is highly recommended to take only the white licensed taxis with a taximeter.
By Car: the centre of Rome it's easily reacheable by car through the Rome-Fiumicino motorway.
By Bus (only night service): Bus stop outside the arrivals halls of the domestic and international terminals. Departures are at 1:15, 2:15, 3:30, 5:00. Tickets can be purchased on the bus from the cost of € 5,00.