Peter Janssen, the leader of animal-rights campaign Vegan Strike Group, was booed by spectators when he leapt into the ring in the French Basque Country city of Bayonne on Tuesday evening.
With the slogan "Macron, you can stop this" daubed on his naked torso, he shouted "Don't mistake barbarism for tradition" and "Macron, our traditions aren't bloodthirsty" before being dragged off by arena employees.
He was taken to the local police station for questioning but released later.
Earlier about 100 anti-bullfight campaigners demonstrated outside the arena and in the afternoon several staged a lie-in in front of the seat of the local council.
Janssen, who is Dutch, has staged about 30 similar protests in bullrings and dolphinariums to protest against "all forms of exploitation of animals for entertainment".
On Saturday he jumped into the ring in Dax, which is near Bayonne.
Tradition or barbarism?
Supporters of bullfighting claim it is a tradition in the south of France, although it is more widespread in Spain, where attempts to ban in the Balearic Islands, the Canary Islands and Catalonia have been blocked by the Constitutional Court.
It is legal in some parts of France, thanks to a law passed in 1951, and was officially part of the country's cultural heritage between 2011 and 2015 when a Paris court annulled the decision.
An alliance of 26 animal-rights groups is campaigning for it to be banned.
A coalition of towns that stage bullfights has accused them of "discriminatory attacks on the community of afficianados, who have the right to respect".
After a bullfighter was killed in the ring in south-west France in June, Enviroment Minister Nicolas Hulot, a veteran green campaigner, confirmed his opposition to the practice.