Tim Brennan is an American musician who is a lead guitarist, vocalist and one of the primary songwriters of the Boston Celtic punk group Dropkick Murphys.

[1] Born in West Hartford, Connecticut, Brennan played drums for numerous punk, hardcore and rock bands in Connecticut where he graduated from Kingswood-Oxford preparatory high school in West Hartford CT in 2000 before moving to Worcester MA to attend Assumption University.

A month after being back in school he got a call that the Dropkick mandolin player had left the band and they asked Tim to join full time.

[citation needed] When Orrell left the Dropkick Murphys, Brennan became the band's lead guitarist, but also continued to play the accordion.

Brennan also played drums in the band Double Nines with Dropkick Murphys' tech Kevin Rheault.