The attack occurred in a hidden area where tigers eat and sleep at around 2 p.m. local time, zoo spokeswoman Naki Carter said.
The tiger was subdued with a tranquilizer and officials treated the injured woman who was rushed to St. Mary’s Medical Center but later died from her injuries, Carter said.
The victim, Stacey Konwiser, 38, had just reached her three-year anniversary at the zoo, where her husband is also a keeper, Carter said.
Konwiser was preparing for a daily educational zoo attraction called Tiger Talks when the incident happened, Carter said.
“Stacy was very passionate toward tigers,” Carter said, adding that zoo workers were in a state of grief. “She was proficient and efficient in dealing with wild animals. Exactly what occurred remains under investigation.”
Carter declined to elaborate on Konwiser’s injuries or the attack itself, which she would only refer to as an “incident.”
The tiger did not escape the enclosure, and no visitors were injured.
The zoo, about 70 miles (113 km) north of Miami, will be closed through the weekend.
The Palm Beach Zoo has four Malayan tigers, an endangered species. Carter said she had no information on what would happen to the tiger.
Word of the attack triggered a frenzy at the zoo, with about two dozen visitors including a number of children being shuffled into the gift shop for protection, a witness told the Palm Beach Post newspaper.