On Tuesday, they caught up with the man at his home east of Paris, but discovered he had left the big cat at another address.
On arriving at an apartment in the northeastern Noisy-le-Sec suburb, the fire service found the abandoned cub "wasting away."
After being captured with a lasso, the startled lion was placed in the care of an animal rights group.
The man was taken into custody on charges of illegally keeping a wild animal.
A series of photographs posted on Facebook by Pompiers de Paris, the Paris fire brigade, shows firefighters and vets carefully placing the fierce-looking cub in a cage.
Their rescue efforts were appreciated by netizens. "Thank you for saving the poor little baby," wrote one person. "Poor baby separated from his mum. Thank you for saving him," wrote another.
This is not the first time a big cat has been found abandoned in the French capital's northern suburbs.
In 2016, a tiger cub was abandoned northeast of Paris, where it was being rented out by drug dealers for a few euros a photo.
(With inputs from AFP) Click for more trending news
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