Liquid Tension Experiment (LTE) is an American instrumental progressive metal supergroup founded by Mike Portnoy in 1997. The band initially released two albums, between 1998 and 1999. An extension of their second regular album, with the absence of John Petrucci was released in 2007 under the name "Liquid Trio Experiment".

Active up until 1999, when Jordan Rudess formally joined Dream Theater, the band reunited in 2008 for a series of live shows. A live album with the absence of Jordan Rudess (mostly) was released in 2009 under the name "Liquid Trio Experiment 2", as were three live albums and two videos featuring the complete band. They regrouped once again in 2020 to record a third studio album featuring all band members, which was released on April 16, 2021.