The First Republic of Korea was the government of South Korea from August 1948 to April 1960. The first republic was founded on 15 August 1948 after the transfer from the United States Army Military Government that governed South Korea since the end of Japanese rule in 1945, becoming the first independent republican government in Korea. Syngman Rhee became the first president of South Korea following the May 1948 general election, and the National Assembly in Seoul promulgated South Korea's first constitution in July, establishing a presidential system of government.

The second Republic of Korea was the government of South Korea from April 1960 to May 1961.