Of some 1.5 million AIDS orphans in the country, a tiny fraction of about 1,900 were adopted by South Africans last year, down nearly 13 percent from the year before, Skweyiya told reporters.
"South Africa is facing a challenge of increasing numbers of orphaned children, abandoned babies, worrying levels of abuse, neglect and exploitation of children," he told journalists in Pretoria.
The government provides support to about 238,000 AIDS orphans and to more than 20,000 homes where older children care for younger siblings after their parents die from the virus, he said.
"Some of these children have assumed adult responsibilities long before they are ready to do so," he said.
Nearly 495,000 AIDS orphans are in foster case, but he said more adoptions are needed so orphans can have permanent families.
"We encourage South African families to adopt children and provide them with permanent families and love. Foster care is a useful short-term intervention but cannot be the only solution," he said.
South Africa is battling one of the world's worst AIDS epidemics, with some 5.5 million of the 47 million population infected by HIV.