Mark Mulcahy is an American musician and former front-man until 1996 for Miracle Legion. Since that band dissolved Mulcahy has released several solo albums, including: Fathering, SmileSunset, In Pursuit of Your Happiness, and the EP Love’s the Only Thing That Shuts Me Up.

As lead singer in the band Miracle Legion, Mulcahy toured the world and appeared on MTV and Late Night with David Letterman. After their demise, Mulcahy composed the music for the Nickelodeon television series The Adventures of Pete and Pete , performing with the fictional TV band Polaris, a group comprised of three-fourths of the Miracle Legion lineup. He has also written music for the films Spring Forward, The Crush, and A Matter of Degrees, and was featured in the Nick Hornby essay collection Songbook. In March 2006 he performed "Don't Talk Crazy" with Michael Stipe at the "Bring ‘Em Home Now" concert in New York City. Mark collaborated with writer/artist Ben Katchor on two musicals, The Rosenbach Company and The Slug Bearers of Kayrol Island, or, The Friends of Dr. Rushower.

In 2013 he released his first full-length album in eight years, Dear Mark J. Mulcahy, I Love You.