Benjamin Griveaux announced on Friday morning that he was standing down from the race to be the next mayor of Paris.
He said: “I don't want to expose myself and my family any further, when every move is now allowed, it's going too far.
“This decision is costing me, but my priorities are clear, it's first and foremost my family.”
He condemned “despicable attacks” but did not comment on the authenticity of the leaked video, which French newspaper Le Monde rather delicately described as “private images of a sexual nature”.
The video was released on Twitter by a little-known website that clams to hold politicians to account.
His resignation adds further chaos to an already unruly race for the job of mayor of Paris.
Current incumbent Anne Hidalgo, of the Socialist party, is fighting off several challengers.
Griveaux, who was previously the official spokesman for the Macron government, was the candidate for Macron's party la République en Marche, but former LREM member Cedric Villani is also standing.
After refusing requests to stand aside for Griveaux, Villani was then expelled from the party and is now standing as an independent.
To see the other candidates and what they have planned for Paris – click here.
The video of Griveaux – which the married father-of-three had allegedly sent to another woman – was leaked online by the Russian performance artist Pyotr Pavlensky who until now was most famous for nailing his scrotum to Red Square.
He was granted asylum in France in 2017 after fleeing from Russia.