Ruiz made her professional debut on , along with her sister Nora Cullen, working as an actress and reader. In the 1940s and 1950s she was known for her narration of radio plays by
Nené Cascallar. She began appearing on stage in 1942. A film career followed later. In 1960 Ruiz starred in
Fernando Ayala's ''
. Other notable films include La Chacota'' (1962), '
(1970), ' (1977), ''
(1980), La historia oficial (1985) and '' (1981). In 1997 the Argentine Association of Actors awarded her the Premio Podestá. ==Personal life==