The two leaders, along with the mayor of Paris Anne Hidalgo, laid flowers at the music venue where 90 people were killed by jihadist gunmen and suicide bombers on November 13.
Helicopters flew overhead and police shut off the roads around the bloodiest scene of the Paris attacks, with security concerns running high as some 150 world leaders were due to descend on the French capital.
The visit to the Bataclan was announced at the last minute after rallies ahead of the climate talks turned violent, as anti-capitalist protesters clashed with police.
Police fired teargas at protesters, who pelted them with bottles and candles in Place de la Republique where a memorial had been set up for the 130 people killed in the Paris attacks. More than 200 people were detained.
The clashes soured the mood before the start of the talks, known as COP21, aimed at clinching the world's first universal climate deal to limit global greenhouse gas emissions.
Earlier on Sunday, Canadian Prime Minister Justin Trudeau also visited the Bataclan with his French counterpart, Manuel Valls, as did the premier of French-speaking Quebec, Philippe Couillard.
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PARIS - US President Barack Obama joined French leader Francois Hollande to pay respects to the victims of the Paris attacks at the Bataclan concert hall early Monday, hours before the official opening of a UN climate conference.