Cesare Romiti's announcement comes a week after he was ordered to stand trial in connection with corruption allegations.
Prosecutors allege Mr Romiti paid bribes to political parties, in connection with contracts for work on the underground railway system in Rome.
![[ image: width=150]](/olmedia/45000/images/_49757_romiti.jpg)
But Mr Romiti, who is 75 in June, denied the impending case was the reason he was leaving Fiat.
He said: "This is nothing more than the confirmation of news that goes back two years when I said that when I turn 75, even if I haven't completed my three-year mandate, I would have left."
Mr Romiti told the Italian news agency, ANSA: "I leave Fiat in excellent condition - in good health, with turnover and profitability on the increase and able to face the future."
A General Electric executive, Paulo Fresco, is set to replace him.
The official announcement of the appointment of Fresco, who has been a board member since June 1996, is expected to be made in a letter to shareholders at the end of January.
Fiat boss accused of corruption
(16 Jan 98 | Business)
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