Many bear the scars of mutilation, wounds from choke-hold leashes and other signs of abuse.
"Here, monkeys learn that they are monkeys," said the center's founder, Elba Munoz, a life-long animal lover who runs the facility with her family.
"When they're in (abusive) homes they aren't monkeys, they can't develop the normal behaviors of their species. So they're not monkeys. And they're not children either. They're nothing," she told AFP, against the din of her patients' shrieks and howls.
Munoz launched the center in 1994 after adopting a monkey herself.
She said it made her realize the horrific treatment exotic animals face at the hands of traffickers and abusive owners.
Animal trafficking is a persistent problem in Chile, where exotic pets are seen as chic status symbols.
Under Chilean law, trafficking in protected species is punishable by up to 60 days in prison and large fines.
But the penalties do not stop a heavy traffic in exotic animals across the Brazilian, Bolivian, Peruvian and Argentine borders.
Monkeys were all the rage in the 1990s, but then the fashion switched to exotic birds like toucans and macaws.
The trend of the moment is iguanas, lizards and boa constrictors, said Carlos Munoz, deputy chief of an investigative division tasked with fighting environmental crimes.
"The reptile market is enormous in Chile," he said.
And monkey trafficking is "still a problem," he said.
Monkey owners put themselves at risk of diseases like rabies and tuberculosis, while reptiles can carry salmonella bacteria, he warned.
Keeping these illegal pets, he said, is bad for owners and animals alike.