Puan was given to Perth zoo in 1968 and is believed to have been born in Sumatra 1956.
Zookeepers have paid emotional tribute to the world's oldest known Sumatran orangutan, "a grand old lady" who died at a Western Australian zoo on Monday.
Puan was euthanised on Monday after suffering age-related complications that the zoo said were affecting her quality of life.
"She did so much for the colony at Perth Zoo and the survival of her species", said primate supervisor Holly Thompson.
Puan was awarded a Guinness Book of Records in 2016 for being the oldest verified Sumatran Orangutan in the world.
Sumatran orangutans are a critically endangered species with about 7,500 left in the world, according to WWF figures.
"Puan is one of the more hard members of our colony to write about - she's not as outgoing as Sekara, as sweet as Utama or as placid as Dinar, but she certainly holds a special place in everyone's hearts, and her legacy is quite simply incredible".
Her genetics count for just under 10 percent of the global captive population.
She has 11 children of her own and is a grandmother and a great-grandmother.
Martina Hart, Puan's chief zookeeper wrote an obituary for the ape in The West Australian newspaper today.
'You always knew where you stood with Puan, and she would actually stamp her foot if she was dissatisfied with something you did'.
"Over the years Puan's eyelashes had greyed, her movement had slowed down and her mind had started to wander".
'But she remained the matriarch, the quiet, dignified lady she had always been'.
Though Puan wasn't as affectionate as some of the other orang-utans, she had a profound impact on all the people who cared for her across the past 50 years.
Ms Thompson said she was an aloof and independent individual.
"She really has seen it all, from the jungles of the wild to the old exhibits here at Perth, to our now world class exhibits".
She leaves behind an incredible legacy that includes 11 children, most of which are now wild orangutans that are each expected to reproduce four times in their lives.