Clarence and his brother Brutus were rescued from a French circus in 2012.
Keepers say they are "proud that she lived as long as she did" as wild lions only live to about 14.
Amali, 2, developed a life-threatening intestinal obstruction, the safari park in Hythe says.
Wingham Wildlife Park has yet to confirm a date when the public can see view the Asiatic lion brothers.
Bertie, Will and Mak travelled miles from Whipsnade Zoo in Bedfordshire to Africa Alive in Suffolk.
Bertie, Will and Mak travel 140 miles to keep alive a zoo's tradition of keeping lions.
There are about 500 to 600 Asiatic lions left in the wild which only live in Gir Forest, India.
The park says the animals have been "peacefully put to sleep" due to age-related health conditions.
BBC reporter Andy Howard comes face-to-face with the kings of Africa, in the Wiltshire countryside.
