The second patient, a 73-year-old woman from Geoje island, has now recovered from the disease, the Korea Centres for Disease Control and Prevention (KCDC) said in a statement.
A 56-year-old man, from the southwest of the country, was the first one to be detected with the disease on Tuesday, EFE news reported.
The KCDC suspects they could have contracted the disease from seafood as the man had reportedly travelled to Geoje island and eaten crabs at a local restaurant, while the second patient, a local resident of the island, had eaten mackerel.
The last cholera outbreak in South Korea was recorded in 2001, when it affected 162 people in the Gyeongsang region.
Cholera, an acute intestinal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae, causes vomiting and severe dehydration and, if left untreated, has a 50 per cent mortality rate.
Cholera is endemic in 50 countries with 1.4 to 4.3 million cases registered worldwide, out of which around 142,000 people die from the disease.
