Maria Rowena Amelia Villena Guanzon (Tagalog pronunciation: [rɔˈwena ˈgwanzon], born August 29, 1957), is a Filipina lawyer, public servant, and politician who notably served as Philippine Commission on Elections commissioner from 2015 to 2022 under President Benigno Aquino III and President Rodrigo Duterte. She had been an audit commissioner before taking office at the Philippine Commission on Elections in February 2015.