Symphony X is an American progressive/power metal band from New Jersey founded in 1994 by guitarist Michael Romeo. Their 1997 album The Divine Wings of Tragedy and their 2000 release V: The New Mythology Suite have gained the band considerable attention within the progressive metal community. Musically Symphony X is similar to although heavier than most other progressive metal bands to which they are commonly compared: Dream Theater, Fates Warning and Pain of Salvation. They play in a very syncopated, progressive fashion, also incorporating elements of symphonic metal into their sound. Their music contains strong neo-classical elements in line with the music of Yngwie Malmsteen, Randy Rhoads and other influential neo-classical metal artists.

The band currently consists of the following musicians: Michael Romeo (Guitar), Russell Allen (Vocals), Michael Pinnella (Keyboard), Jason Rullo (Drums), Michael Lepond (Bass).

Former members:
Rod Tyler (Vocals), Thomas Miller (Bass), Thomas Walling (Drums)

To date, the band has recorded 7 studio albums and also released one Live-CD, Live on the Edge of Forever. Symphony X latest album was released June 2007, entitled Paradise Lost.