32-year-old Myah Autry is being held in the 52nd precinct, pending charges.
A bystander's Instagram videos showed the incident last month.
The zoo said it has a "zero-tolerance policy" for this type of behavior.
"This action was a serious violation and unlawful trespass that could have resulted in serious injury or death. Barriers and rules are in place to keep both visitors, staff, and animals safe," the zoo said in a statement.
The park told police that there is a moat with an approximately 14-foot drop between where the woman was standing in the video and the lion.
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