Rex Robert Brown (born July 27, 1964) is an American musician and author, who is best known as having been the longtime bassist for the Grammy-nominated, platinum-selling, now defunct band Pantera (1982–2003). He is a former member of Down (2001–2011), and is currently the bassist for the band Kill Devil Hill. He released his debut solo album ˝Smoke On This˝ on July 28th, 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 break-up.