Maria Lourdes "Meilou" Aranal Sereno (Tagalog: [s?'r?n?], born Maria Lourdes Punzalan Aranal; July 2, 1960) is a Filipina lawyer and judge who served as de facto Chief Justice of the Supreme Court of the Republic of the Philippines from 2012 until her removal in 2018.
Appointed as Associate Justice by President Benigno Aquino III in August 2010, she became the second youngest person (at the age of 52) to assume the post of Chief Justice in August 2012.
She was removed from office by way of an 8–6 decision by the Supreme Court over a quo warranto petition, rendering her appointment as Chief Justice null and void.
Many supporters as well as legal experts regard the removal of Sereno, who opposed President Duterte's martial law and other executive actions, as politically motivated.