Forest rangers in the central region's Quang Ngai Province confiscated a rare douc langur being held by a woman at home on Wednesday.
The langur is a male one, more than 5 years of age and around 10 kilograms.
It was being kept by local resident Huynh Thi Thanh, said Nguyen Van Han, head of the Quang Ngai Province forest management department.
The animal is listed in Vietnam's Red Book as extremely endangered. The animal can now only be found along the Truong Son Mountain Range in the central region.
Thanh said she bought the langur from local children not long go when it was very weak and she asked local animal health officials to take care of it. The children found the animal while pasturing cattle, she said.
The resident agreed to hand over the langur after being told that keeping endangered animals at home is illegal.
Quang Ngai forest rangers have contacted Ho Chi Minh City Zoo and Cuc Phuong National Park, around 100 kilometers from Hanoi, to see if they can receive the langur.