Asesinos Cereales formed in 2000 shortly after the separation of the local scene bands Bajo Presion , Hating Hate and Alteración . Initially, the new band was still influenced by the music of the former groups, the punk rock. But the musicians continued to develop and broaden the horizons of their music. She started to experiment with ska rhythms and also trumpet, trombone and keyboard found their place in some pieces. During the concerts she played with Ska-P , The Locos and the Reincidentes .

In January 2005, they began recording their first CD called Rompecabezas. Produced by 4K Records and distributed by Universal , this first disc contained 12 tracks. In the second half of 2005, the Asesinos Cereales played with The Locos and the Reincidentes from Spain.

The second CD of the Asesinos Cereales Sin Fronteras was released in November 2007. In addition to this CD, a video clip was shot to Podria Ser Viernes .

In Germany, they became known primarily as friends of Ska-P , as they frequently performed with them and also cover live plays.