Tanzi is the first executive to be sent to prison for his part in the firm's collapse
The founder of Parmalat, Calisto Tanzi, has been sentenced to 10 years in prison for fraud relating to the collapse of the dairy group.
Tanzi was accused of manipulating the share price, hindering auditors and helping with false accounting.
Parmalat collapsed in 2003 with a 14bn euro ($20bn; £13bn) hole in its accounts in what remains Europe's biggest bankruptcy.
The other seven defendants, including executives and bankers, were acquitted.
Another eight defendants settled out of court in September.
More than 40,000 investors are seeking compensation for losses.
The court will now decide whether Tanzi should pay damages to them.
Parmalat was restructured and relisted on the Milan stock exchange in 2005 and is once again Italy's biggest market-listed food group.
It has recouped money from its banks in settlements since the collapse.
Tanzi will probably not begin his jail term straight away because under Italian law the sentence of the Milan court must be confirmed first by an appeals court.
Tanzi is also a defendant in a separate trial under way in Parma, where he is accused of fraudulent bankruptcy.