Legislative elections were held in South Korea on 13 April 2016. All 300 members of the National Assembly were elected, 253 from first-past-the-post constituencies and 47 from proportional party lists. The election was an upset victory for the liberal Democratic Party, which defied opinion polling by winning a plurality of seats in the election and defeating the ruling conservative Saenuri Party by one seat. In votes for party lists, however, Democratic Party came third, behind the Saenuri Party in first place and the new People Party in second.

The National Assembly of the Republic of Korea, often shortened to the National Assembly, is the unicameral national legislature of South Korea. Elections to the National Assembly are held every four years. The latest legislative elections was held on 10 April 2024. The National Assembly has 300 seats, with 253 constituency seats and 47 proportional representation seats; 30 of the PR seats are assigned an additional member system, while 17 PR seats use the parallel voting method.