Sergio Eduardo Diez Urzúa (2 April 1925 – 29 June 2015) was a Chilean architect and politician.

He is commonly remembered for having denied that arrested people disappeared during Pinochet dictatorship (1973–1990).

[1][2][3][4] His parents were former Congressman Manuel Diez García and Yolanda Urzúa Ravanal.

He graduated from the San Martín de Curicó Institute, belonging to the Congregation of the Marist Brothers, and then from the Faculty of Law of the Pontifical Catholic University, of which he graduated as a lawyer in 1948.

[5] In 1948, he was secretary general of the Conservative Party and then a member of its Executive Board.