CANBERRA, Aug 2 (Reuters) - A 94-year-old Australian great-great-grandmother who quit school at 12 is said to have become the world's oldest person to earn a university masters degree.

Medical Science Masters Degree graduate Phyllis Turner, from Australia's Adelaide University, began studying for her postgraduate degree at age 90 and received her award this week.

"I feel very very happy after five years of study, but sorry that I am just a little bit immobilised," Mrs Turner, who uses a walking stick, told Australian papers.

Degree supervisor Professor Maciej Henneberg said he had been amazed by Turner's energy and dedication to study.

"Mentally she was like any other student. You couldn't tell her thinking, her enthusiasm and her interests apart from somebody who was 25. She has a lively mind," he told Reuters.

"She used to wake up at 5am in the morning and think about something, and then ring to say she wanted to check on it."

Turner left primary school at 12 to help her mother look after her siblings after her father left the family.

She returned to study almost 60 years later, enrolling at the prestigious Adelaide University to study anthropology at age 70, winning honours in 2002 before moving on to her masters.

Henneberg said Turner completed a research based paper into the anthropological history of Australia prior to European settlement and international investigations showed she was the oldest postgraduate degree recipient in the world.

"We will be trying to enter her into the Guinness book of world records, he said.