Rex Robert Brown (born July 27, 1964) is an American musician, best known as the longtime bassist for heavy metal band Pantera (1982–2003). He is a former member of Down (2001–2011) and the former bassist for the band Kill Devil Hill. He released his debut solo album Smoke on This… in 2017. For the first time in Brown’s career, the work features him not only as a bassist but also as lead vocalist and guitarist.

Brown authored a book called Official Truth 101 Proof, which was released in April 2013. The book documents Pantera’s formation, career, and disbandment.

Pantera was formed in 1981. Brown joined Pantera on bass in 1982 replacing Tommy D. Bradford and adopting the alias « Rex Rocker« . Brown was a classmate of, and played in the high school jazz band with, drummer Vinnie Paul, and guitarist Dimebag Darrell (then known as Diamond Darrell). Brown was credited as « Rex Rocker » on Pantera’s first four albums: Metal Magic (1983), Projects in the Jungle (1984), I Am the Night (1985), and « Power Metal » (1988),[6] he would be credited by his birth name starting with the band’s fifth album Cowboys from Hell and onwards.

Pantera recruited vocalist Phil Anselmo to replace Terry Glaze in 1987. With Anselmo taking over as the new frontman, the band’s fourth album, Power Metal, was released in 1988. By 1990, the band had been signed with Atco Records, and released their fifth album, Cowboys from Hell, which proved to be the band’s turning point to commercial success. Over the course of the band’s walkthrough in the 1990s decade, Pantera released four more studio albums, Vulgar Display of Power (1992), Far Beyond Driven (1994), The Great Southern Trendkill (1996), and Reinventing the Steel (2000). After releases of a 1997 live album and a greatest hits compilation, Pantera was nominated for four best metal performance Grammys, for « I’m Broken », « Suicide Note Pt. I », « Cemetery Gates », and « Revolution Is My Name ».

In 2001, Pantera went on what at the time was believed to be a temporary hiatus, mainly due to Anselmo’s focus on side projects. Pantera would officially disband in 2003.