Mauricio Aznar Müller (January 26, 1964 – October 2,[1] 2000) was an Aragonese poet and musician, leader of the bands Golden Zippers, Más Birras and Almagato.

In 1984 he created Más Birras, the group with which he would achieve solid prestige after Jesús Ordovás released in Radio 3 the song «Apuesta por el rock and roll», included in the maxisingle Al este del Moncayo (1987), written by Gabriel Sopeña and later popularized by Héroes del Silencio, which made it an Aragonese rock classic.

However, Mauricio Aznar began to get interested about Argentinian tango and other forms of their folklore, that combined to the not so successful last disc of Más Birras, led to the group dissolution in 1993.

In his last years, and as instigator of the Almagato group, together with Jaime González, he dedicated himself to spreading the folklore of Santiago del Estero and other regions of northwestern Argentina, cultivating genres such as chacareras, zambas or vidalas.

Before dying, he delivered a book with manuscripted poems to Javier Barreiro; and left around twenty unreleased songs composed with his close friend Gabriel Sopeña.