Rosalía de Castro (24 February 1837 – 15 July 1885) was a Spanish writer and poet.

A native of Santiago de Compostela in the Galicia region of northwest Spain, she wrote in both Galician and Castilian.

Writing in Galician language, after the Séculos Escuros (Dark Centuries), she became an important figure of the Galician romantic movement, lately named Rexurdimento, along with Manuel Curros Enríquez and Eduardo Pondal.

She married Manuel Murguía, member of the Galician Academy, journalist and editor of Rosalía's books.

The date she published her first poetry book in Galician, Cantares gallegos, May 17th 1863, is remembered every year. It is the Día das Letras Galegas (Day of the Galician Letters) and dedicated to an important writer in Galician language since 1963.

Her image appeared in Spanish bank notes worth 500 pesetas.