The cat, roughly 6 months old, was found prowling along the window ledges in Armentières, near Lille, and lounging around for nearly an hour.
Authorities tried to rescue the panther, which was owned by a local resident, the BBC reported, citing local media.
Before it was captured, the black panther reportedly walked the stairs of the building it was prowling around and entered an apartment, frightening a teen girl inside. A veterinarian eventually was able to tranquilize the animal.
The domesticated black panther was not aggressive, had its nails clipped and was in good health, according to Kader Laghouati, of a local animal rescue.
Investigators are trying to speak with the owner of the big cat about how the animal got out, where it came from and what conditions it's being held in in France. A source told La Voix du Nord, a French newspaper, that only a zoo would be able to get a permit to keep a black panther.