Mercedes Capsir (Catalan pronunciation: [məɾˈsɛðəs kəpˈsi]; 20 July 1895 – 13 March 1969) was a Catalan opera singer, a high coloratura soprano, particularly associated with light Italian roles, such as Lucia and Gilda.

She studied (piano, composition, voice) at the Conservatori Superior de Música del Liceu, before making her debut in Genora, in 1913, as Gilda in Rigoletto, a role she will remain closely associated with throughout her career.

Her Italian debut took place in Bologna, as Rosina in Il barbiere di Siviglia, followed by Elvira in I puritani, in Venice, opposite Giacomo Lauri-Volpi, she also appeared in Rome, before reaching La Scala in Milan, in 1924, again as Gilda, opposite baritone Carlo Galeffi and tenor Miguel Fleta, and conducted by Arturo Toscanini.

Capsir retired from the stage in 1949, her final performance took place at the Liceu in Barcelona, as Carolina in Il matrimonio segreto, and then turned to teaching.

Mercedes Capsir recorded in 1928, complete versions of Il barbiere di Siviglia and Rigoletto, opposite Riccardo Stracciari and Dino Borgioli.