The National Plebiscite of 1980 in Chile was a referendum held on September 11, 1980 in order to approve the 1980 Political Constitution of the Republic of Chile as a replacement for Chile’s 1925 constitution. The result was 4,204,897 (67.04%) votes in favor and 1,893,420 (30.19%) votes against ratification. This plebiscite has been, and continues to be, questioned regarding irregularities in its management.

This election made way for the military regime of Augusto Pinochet, solidifying his position as President of the Republic (with increased powers) for 8 years, when he would face a yes-or-no reelection plebiscite.