The 37-year-old tested positive for the banned blood booster erythropoietin in an out-of-competition test taken at his home in April, five days before the start of this year's Giro.
He had previously been suspended for three months in 2007 for frequenting a doctor banned for his involvement in doping and received a two-year ban reduced to 15 months for a positive EPO test at the 2009 Giro.
The 2007 Giro winner was sacked this May by his Vini-Fantini team, who said they would be seeking compensation from a rider they feared could cause problems given his past.
He was provisionally suspended pending Thursday's decision by the Italian tribunal.
A statement said he was also fined 35,000 euros (£29,300) as well as being ordered to pay the costs of the proceedings.
Italian cyclists have been involved in drugs scandals more than most in the doping scourge which wreaked havoc across the sport in the last 20 years but being banned three times marks out Di Luca as one of the most caught offenders.
Even Lance Armstrong, who had his seven Tour de France titles stripped before he confessed to systematic doping, said Di Luca was beyond the pale.
"Knowing I have 0 cred on the doping issue - I still can't help but think, 'really Di Luca? Are you that....stupid??'" the American tweeted in May.
- Sports & Recreation