The wife of former President Laurent Gbagbo has been charged along with 82 supporters of her husband. Mr Gbagbo is awaiting trial at the International Criminal Court (ICC) on charges of crimes against humanity.
Some 3,000 people died in violence after the ex-president refused to accept defeat in a run-off vote.
Mrs Gbagbo, who had been held under house arrest for three years, has been charged with “attempting to undermine the security of the state”.
Former prime minister Gilbert Ake N’Gbo and Ivorian Popular Front (FPI) party head Affi N’Guessan are also being tried along with the former first lady.
Her husband, ex-President Laurent Gbagbo, is facing four charges at the ICC in The Hague, including murder, rape and persecution. Mr Gbagbo, 69, who insists he is innocent, is the first former head of state to have appeared at the ICC.
Mrs Gbagbo has also been accused by the ICC but Ivory Coast has refused repeated requests to hand her over, saying that she should be tried in a domestic court.
She was arrested in 2011 after troops stormed a bunker in which she and her husband had taken refuge, following a military assault on their residence in the main city, Abidjan.
Violence broke out in Ivory Coast in 2010 when Laurent Gbagbo refused to cede power to his rival Alassane Ouattara, who was declared the winner of a presidential poll.
The West African leader was ousted in 2011 with the help of French and UN forces backing President Ouattara.
Proceedings at Mrs Gbagbo’s trial on Friday were expected to be limited to jury selection, with hearings beginning properly next month.
