Mariano Javier Castro (born 31 January 1978), known professionally as Dread Mar I, is an Argentine singer of reggae rock, reggae en Español, ska and pop music.

Born in Quequén, Argentina, Castro dropped out of school in the seventh grade and moved to Maipú, Buenos Aires to work in his father's bakery.

After a decade in the town, he travelled to Buenos Aires where he eventually began making music.

[1] In 2005, Castro began performing as a solo artist under the name "Dread Mar I", and released his first album Jah Guia.

The performance was recorded under an album called 10 años (en vivo) , and released at Estadio Luna Park.