The fatal attack happened at the Hellbrunn zoo in the western Austrian city of Salzburg.
Zoo director, Sabine Grebner, told reporters later on Tuesday that the 33-year-old woman, a German citizen from Bavaria, was assigned that day to put an insect deterrent on the rhino.
It was then that 30-year-old female rhino, Jeti, attacked the keeper though it was not clear why, Austria’s APA news agency cited Grebner as saying.
Salzburg police said that "the woman succumbed to her injuries at the scene of the accident."
The other zookeeper, a 34-year-old Austrian citizen, was also attacked and injured when he tried to chase the rhino away from his wife.
The woman suffered severe chest trauma because of the attack and died in the enclosure while her husband had a fractured leg and was taken to the hospital, APA reported.
The names of the two zookeepers were not given in line with Austrian privacy rules.
The zoo director said the fatally injured keeper was known to be "very careful and thoughtful with the animals, and she had an extremely good sense" when dealing with them.
Grebner said the exact circumstances of how the accident occurred had yet to be determined.
"We don't know what exactly happened," she said. "We are deeply upset and shocked."
All safety regulations would get re-evaluated, she said, adding that there had been no previous incidents at the rhino enclosure which was set up nearly 30 years ago.
The zoo will remain closed on Tuesday.