Lucía Sánchez Saornil (13 December 1895 – 2 June 1970), was a Spanish poet and anarcha-feminist activist, best known for co-founding the Mujeres Libres organisation together with Mercedes Comaposada and Amparo Poch y Gascón.

During the Spanish Civil War, she continued her work with the Mujeres Libres and also served as secretary of Solidaridad Internacional Antifascista (SIA), making frequent trips to the frontline and campaigning for international support for the Republicans.

[1] Following the proclamation of the Second Spanish Republic in 1931, Sánchez Saornil participated in a strike action [ca] against Telefónica, which first brought her into the Confederación Nacional del Trabajo (CNT).

Sánchez Saornil responded with her own series of five articles titled "La cuestión femenina", which lay the groundwork for the establishment of a libertarian women's organization.

[8] These discussions set the groundwork for the establishment of the Mujeres Libres organisation,[4] which Sánchez Saornil and Comaposada co-founded with the anarchist physician Amparo Poch y Gascón.

[12] Following the outbreak of the Spanish Civil War, Sánchez Saornil joined in the defense of Madrid, working as a front line journalist and propagandist for the anarchists.

[13] Her writing attracted the attention of the anarchist Emma Goldman, who corresponded frequently with Sánchez Saornil, inspiring her to coordinate an international campaign to support the Spanish revolution.

[15] She became the general secretary of Solidaridad Internacional Antifascista (SIA) and made regular supply trips to the front-line,[16] along with other Mujeres Libres and women of the CNT.

In a letter to the CNT's national committee, Sánchez Saornil wrote:[21] "It is a pity that you compañeros have always had so little time to acquaint yourselves with the valuable work of Mujeres Libres and that the consequence of this is the little interest you have shown in responding to our plea.

"Sánchez Saornil also dismissed calls by the Communist-led Association of Antifascist Women [es] to unite under their banner,[22] as she believed the organisation was more than capable of continuing its direct action and consciousness raising without requiring standardisation within a state structure.

"In February 1939, Catalonia fell to the Nationalists, forcing Sánchez Saornil to flee into exile in France, where she was briefly held in the Argelers concentration camp.

[23] Sánchez Saornil spent much of the rest of her life caring for her sister Conchita, who had a chronic condition, and lived for 30 years with her partner América Barroso.