News that he was being held was broken by a Gbagbo aide and confirmed by France's ambassador and forces loyal to his rival Alassane Ouattara.
French tanks earlier advanced on the presidential residence in Abidjan.
Mr Gbagbo has been refusing to cede power to Mr Ouattara after losing November's presidential election.
There were conflicting accounts about how Mr Gbagbo had been captured, with France's ambassador saying he had been taken by troops loyal to Mr Ouattara and an aide to Mr Gbagbo saying French special forces had been involved.
A spokesman for Mr Ouattara told Reuters that Mr Gbagbo had been taken to the city's Golf Hotel, where Mr Ouattara has his headquarters.
UN peacekeepers have accused Gbabgo forces of endangering the civilian population, and had asked French troops in Ivory Coast to act against the defiant leader's heavy weapons.
Forces loyal to Mr Ouattara launched an offensive from their stronghold in the north at the end of March, after months of political deadlock during which Mr Gbagbo refused to recognise his rival's election victory.
As they closed in on Mr Gbagbo's power base in Abidjan, UN and French attack helicopters targeted heavy weapons being used by his forces.
Attempts to negotiate his exit failed, and his forces appeared to be making a comeback by the end of last week, even threatening the hotel used by Mr Ouattara.
On Sunday, UN and French helicopters launched a new wave of air strikes, and on Monday French tanks were seen advancing on the residence.
France's ambassador to Ivory Cost, Jean-Marc Simon, told AFP news agency: "Laurent Gbagbo was arrested by the Republican Forces of Ivory Coast and taken to the Golf Hotel."
AFP added that eyewitnesses had seen pro-Ouattara forces entering the presidential compound while French and UN armoured vehicles stood on a road leading to the complex.
However, an aide to Mr Gbagbo, Toussaint Alain, told Reuters news agency from Paris: "Gbagbo has been arrested by French special forces in his residence and has been handed over to the rebel leaders."
An unnamed French government source denied the report.
"Mr Gbagbo was arrested by Mr Ouattara's troops, that is true, but not by French special forces, who did not go into the enclosure of Mr Gbagbo's residence," the source told AFP.
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