Catherine Langeais, born Marie-Louise Terrasse, (9 August 1923 in Valence, Drôme – 23 April 1998 in Mantes-la-Jolie, Yvelines), was a French television presenter and actress. Her father was André Terrasse (1890-1951), an economic journalist and secretary to the Alliance démocratique, and her mother was Marthe Brossette, daughter of François Brossette, mayor of Givors.

The family lived in Paris from 1933. On 28 January 1938, at the age of fourteen, when Marie-Louise was at a school dance, she was introduced by her brother to the politician and future president of the French Republic François Mitterrand. In March 1940, in spite of her youth, they became engaged, but they separated on 15 January 1942, when the Germans occupied France.