Osvaldo Sotomayor Ilabaca was the 15th Mayor of the commune of Pichilemu, office which he held between February and March 1935, for a span of only nine days, under President Arturo Alessandri Palma. Sotomayor's mayoral term is the shortest in the history of Pichilemu, excluding acting mayor Gustavo Parraguez Galarce.