Composer Guillermo Martínez began his musical education as a boy singer of the Escolanía de Covadonga, these days when he discovered his vocation for musical creation.

With a degree in composition from CONSMUPA (Spain) and a Master's Degree in composition from The University of Manchester (UK) with honors, Martínez is instructed in the art of composition with teachers Leoncio Diéguez, Brian Ferneyhough and Richard Whalley. His postgraduate degree is awarded with a Cajastur Scholarship for Artists.

As an organist, he trained with teachers Antonio D. Corveiras, Miguel A. del Barco, Andres Céa and Jean Claude Zendher, performed concerts in Europe, recorded Symphony No. 3 "The Organ" by Camille Saint-Saëns for the Warner Classics label. and, he is titular organist of the Cathedral of Oviedo (2018-2022).

In parallel, Martínez develops a profuse activity as a singer. Member of EuropaChorAkademie  (2000-2016), he participates in more than sixty choral and symphonic choral projects under the baton of great figures such as Gielen, Penderecki, Ashkenazy, Frühbeck de Burgos, Plácido Domingo, Cambreling and Vladimir Jurowski, performing in the main concert halls of the USA, China and Europe. Also a member of the “El León de Oro” Choir (2000-2009), he participates in innumerable concerts throughout Europe as well as in the USA, winning the Grand National Prize for Choral Singing on two occasions (2003, 2006) between many other national and international recognitions.

As a composer as a main facet and vocation, Guillermo Martínez has a catalog of more than 100 works in all genres (opera, zarzuela, cantata, symphonic poem, concert,...) and his music has been performed in the USA, Russia , Cuba, Austria, United Kingdom, Germany, Italy, France, Sweden, Switzerland, Hungary, Lithuania, Ukraine, Morocco, Spain… Among the interpreters of his works are the directors Joshard Daus, Marzio Conti, Davide Levi, Lucas Macías, Isabel Rubio, Jean-François G. Hamilton, Luis Miguel Méndez, Rubén Díez and a long etcetera. To these are added the instrumentalists Horacio Lavandera, Iván Martín, Agata Daraskaite, Rolanda Ginkute, Erika Litván, Gerard Claret, Gabriel Ureña, Óscar Martín, Valeria Zorina, Manuel Burgueras and Aurelio Viribay to mention just a few, in addition to the singers María José Montiel , Natalia Troshina, Helena Sorokina, Beatríz Díaz, David Menéndez, Lola Casariego, María José Suárez and Francisco J. Sánchez, among others.

Likewise, his music has been premiered and performed by institutions such as EuropaChorAkademie, St. Christopher Chamber Orchestra, Choir and Orchestra of the Opera of kyiv, Harper Symphony Orchestra, Giusto Chamber Orchestra, Orquesta OFIL, OSPA, Janus Orchestra, JOSPA, Ensemble Ars Mundi , Cuarteto Vocal Español (Coro de  RTVE),  Cuarteto  Vocal  Cavatina,_cc781905-5cde -3194-bb3b-136bad5cf58d_ Psappha Ensemble, Quatuor Danel, Vínculos Quartet, Khorikos – NY, “El León de Oro” Choir, “Ciudad de Oviedo” Music Band, Seville Municipal Symphony Band, Choir of the “Princess of Asturias Foundation ”, Landarbaso Koroa, Ad Solem Chamber Ensemble, “Ángel Barja” Choir - JJMM ULE,  Choral Camerata of the University of Cantabria, University Choir of Oviedo,…

Guillermo Martínez has received various awards (First National Composition Prize - City of Oviedo, RTPA Critics Award, Ortus International New Music Competition,...) and his work has been published in sheet music, CD and DVD. In addition, his music has been broadcast on radio and TV in America and Europe.