Ma Ying-jeou is a frontrunner in the race for president

He is accused of misappropriating T$11.2 million ($339,000) of funds while mayor of the capital, Taipei.

Mr Ma resigned from his position as head of the Kuomintang party shortly after the charges were announced, but said he would clear his name.

He has denied graft charges, and is a frontrunner in the presidential race.

Presidential pledge

Mr Ma, who studied law in Taiwan and the US, is expected to defend himself. He was in confident mood as he arrived at court.

"I am confident of my innocence and I trust in the justice of the court," he said, as a crowd of Kuomintang (KMT) supporters cheered.

Mr Ma was charged with improper use of government funds in February - and resigned as KMT chairman, protested his innocence and pledged to stand for president all at once.

He is facing four rivals from the ruling Democratic Progressive Party (DPP) who are seeking nomination from their party.

The candidates are Vice President Annette Lu, Premier Su Tseng-chang, former premier Frank Hsieh, and former party chairman Yu Hsyi-kun.

The investigation into his finances began in mid-November after allegations that he had shifted money from a special fund into a personal account during his time as mayor, from 1998 to 2006.

If convicted, he would face at least seven years in prison. However, prosecutors have already asked for leniency because of his co-operation with the investigation.