About a million dogs are eaten a year on the carousel, often as a summer dish that is usually boiled for a softer meat believed to increase energy.
However, the tradition has come under criticism abroad and consumption rates have decreased, as many residents have started to make dogs as pets, not as livestock.
Eating meat is now taboo among South Korean youths.
The operation was carried out over two weeks by the animal protection group Humane Society International (HSI). About 200 dogs at a dog farm in the Hongseong area, 150 kilometers south of Seoul, were rescued.
The dogs will then be sent to Canada and the United States (US) for repatriation.
“These dogs are no different from any other dog, once they receive the loving attention they deserve and need,” Kelly O’Meara, an HSI official, told AFP Thursday.
The slaughterhouse is the 14th complex the group has closed since 2015.
The organization has rescued about 1,600 dogs, and the farmers have been given support to move to other occupations. Some have even turned their dog meat business into a blueberry farm.
Lee Sang Gu, the owner of Hongseong farm, admitted that he decided to change his business because it was no longer profitable. Even his family, he said, was against eating dogs.
According to a 2017 survey, as much as 70 percent of South Koreans don’t eat dogs; and about 40 percent believe this practice should be outlawed.
The country’s largest dog slaughterhouse complex is in Seongnam City, south of Seoul, and was demolished in November. Activists who visited found electrical equipment and piles of dead dogs left on the floor.