South Korea holds elections for the following governing organs:
- the President of the State (every five years);
- the members of the National Assembly (every four years);
- the members of all local public assemblies (every four years).
For elections, South Korea uses the following electoral methods:
- Presidential elections: plurality voting. Under plurality voting, people vote in a single round for their favored candidate and the candidate who obtains the largest vote tally is elected to office.
- Parliamentary elections: hybrid electoral system. 253 MPs are elected in first-past-the-post single-member constituencies (plurality voting), and 47 MPs are elected from a nationwide multi-member constituency according to a closed-list proportional representation system. Political parties must include 50% of women in their PR lists. Voters cast two ballots each.
- Local elections: hybrid electoral system (plurality voting and proportional representation).
Sources:
https://www.nec.go.kr/engvote_2013/main/download.jsp?num=598&tb=ENG_NEWS