Eusebio Delfín Figueroa (1 April 1893 in Palmira – 28 April 1965 in Havana) was a Cuban banker and musician. He came from an empoverished aristcratic family, and was trained as an accountant in Cienfuegos, where his family had moved. He also studied guitar and song, and sang in public for the first time in 1916 at the Terry Theatre in Cienfuegos.
Delfín studied violin and flute, but soon switched to guitar and song. His guitar teacher was Fernando Barrios, and his singing coach was Vincente Sánchez Torralba.
Beginning in 1921, he recorded many Cuban songs, both solo and in duets with partners such as Rita Montaner. The first 78rpm with Montaner was Pensamiento (by Rafael Gómez, 'Teofilito'). In 1922 he organised, with Eduardo Sánchez de Fuentes, concerts of typical Cuban music in Havana and Cienfuegos. A relatively wealthy man, Delfín donated much of his royalties to charity in Cienfuegos.
According to Guyún, Delfin was responsible for changing the style used to accompany boleros. In the 1920s, boleros were often accompanied by guitar in rayado or rasgueado manner (~strumming); Delfin changed that to a semi-arpeggio style (~picking). He also repeated the rhythm by time and a half, leaving the weak part of the second beat silent. His style became widely popular. His compositions include poetry put to music, such as La Guinda, from a poem by Pedro Mata, and he also wrote his own lyrics, such as Y tú qué has hecho? (aka En el trunco de un árbol.), Ansia and Qué boca la tuya 
At the soirées of the rich he sang boleros, with the result that the wealthy young became enthusiastic about the guitar.
- Orovio, Helio 2004. Cuban music from A to Z. Revised by Sue Steward. ISBN 0-8223-3186-1 A biographical dictionary of Cuban music, artists, composers, groups and terms. Duke University, Durham NC; Tumi, Bath. p66
- Giro, Radamés 2007. Diccionario encyclopédico de la música en Cuba. vol 2, La Havana. p14
- Reissue of some original recordings is available on Tumbao TCD 088 Eusebio Delfín: En el tronco de un árbol 1924–1928.
- Canizares, Dulcila 1995. La trova tradicional. 2nd ed, La Habana. p89. A more detailed list is given by Radames Giro.
- Sublette, Ned 2004. Cuba and its music: from the first drums to the mambo. p306 Chicago.
- Ezequiel Rodríguez 1966. Homenaje a Eusebio Delfín. La Habana.