The woman who lost her arm in a lion attack at a Queensland zoo is the sister of the owner, Stephanie Robinson.

The woman, described by the zoo as a "member of the family" was watching keepers in the enclosure when one of the animals attacked.

A woman has sustained severe injuries to an arm when she was attacked by a lion at an Australian zoo. The Darling Downs Zoo in Queensland said the 50-year-old woman was watching animal keepers working in the zoo's carnivore precinct before opening hours Sunday morning when she was attacked.