Ms Kelly is the second appointee to the board with "extensive knowledge of the health and aged care industries", said a statement by Prime Super.
She is also the chief executive of Lutheran Care Community (LCC), which employs 1,200 staff and provides services to 2,000 people in Queensland.
Before joining LCC, Ms Kelly accumulated 20 years' experience in senior roles at PricewaterhouseCoopers, Queensland Treasury and Lend Lease Advisor Services, among others.
Prime Super chair Alan Bowman pointed to Ms Kelly's "wealth of knowledge and experience in the aged care industry and commercial life".
"Her commitment to ensuring all Australians have the opportunity to age well and live dignified lives as valued members of the community, makes her a perfect fit for Prime Super," Mr Bowman said.
Prime Super now has a majority of independent directors as well as one union-nominated director and one employer-nominated director.
"There is a growing push in the industry to make industry super fund trustee boards more independent," Mr Bowman said.
"Prime Super remains ahead of the curve on this important governance issue. Our board is already largely independent and this structure allows us to remain focused on members’ best interests."
