Michael Gallagher is an American guitarist, best known for his work with post-metal band Isis.

He joined them in 1999 for their debut LP Celestial, having previously been a member of Cast Iron Hike.

[2] He has an ambient project known as MGR (Mustard Gas & Roses); under this moniker he has released two albums and scored one film.

[3][4] He plays a '78 Les Paul Custom, which he bought on eBay,[5] through a Fryette Sig:x Amplifier.

While playing in Isis he normally tuned his guitar down to (B-F#-B-E-G#-B), like his bandmate Aaron Turner.