Brian Baker (born February 25, 1965) is an American punk rock musician. He is best known as one of the founding members of the hardcore punk band Minor Threat, and as a guitarist in Bad Religion since 1994. In Minor Threat, he originally played bass guitar before switching to guitar in 1982 when Steve Hansgen joined the band, and then moved back to bass after Hansgen's departure. He also founded Dag Nasty in 1985, was part of the original line-up of Samhain, and has had stints in Doggy Style, The Meatmen (with fellow Minor Threat member Lyle Preslar), Government Issue, and Junkyard (a hard rock band).