Carnivore team leader Lauren Booth said it would be "a very quiet Pridelands without their wonderful calls and we will miss their watchful faces".
"But they have left a wonderful legacy in the cubs they have had, the public they have inspired and the memories they leave with us."
Senior vet manager Dr James Chatterton says that it was becoming evident Kura's quality of life was beginning to deteriorate.
"Her decline was irreversible and would only worsen in the days ahead, making euthanasia the kindest, most humane and only option."
Over the past few months the zoo's carnivore keepers and vets had been closely monitoring Kura's health, as despite an increased diet she was having trouble maintaining her weight.
While matriarch of the pride her entire life, she also tellingly began displaying behaviours that indicated she was feeling extremely vulnerable, including for the first time, acting submissively towards her daughter Amira.
Kura and Amira were the last lions left in Auckland Zoo’s pride, after 19-year-old Sheeka was put down in November last year.