This study analyzed the legislative productivity of the 19th National Assembly after the application of the National Assembly Advancement Act, confirming that legislative activities shifted from a government-ruling party focus to a cooperative system involving the government, ruling party, and opposition. Specifically, the proportion of parliamentary legislation tripled, and the proportion of opposition legislation increased more significantly than that of the ruling party, demonstrating the operation of cooperative politics between the ruling and opposition parties. The approval rate of government bills and the legislative activities of lawmakers differed depending on the party affiliation of the standing committee chairpersons.