Neurosis is an American post-metal band from Oakland, California. It was formed in 1985 by guitarist Scott Kelly, bassist Dave Edwardson, and drummer Jason Roeder, initially as a crust punk band. Chad Salter joined as a second guitarist and appeared on the band's 1987 debut Pain of Mind and then Steve Von Till replaced him in 1989. The following year, the lineup further expanded to include a keyboardist and a visual artist. Beginning with their third album Souls at Zero (1992), Neurosis transformed their hardcore sound by incorporating diverse influences including doom metal and industrial music, becoming a major force in the emergence of the post-metal and sludge metal genres.

The band's lineup stabilized in 1995 with the addition of Noah Landis, who replaced Simon McIlroy on keyboards and electronics. That same year they formed the experimental music group Tribes of Neurot and in 1999 the record label Neurot Recordings. This line-up remained stable until 2019, when the band parted ways with Kelly after discovering his history of domestic violence against his family, though this would not come to light until August 2022 out of respect for the privacy of Kelly's family members. The band has been on hiatus since then, and there is currently no information on whether or not the band will continue or disband.

Neurosis have garnered critical recognition over the course of their 11 studio albums. The BBC credited them with taking "heavy music to previously unimaginable spaces ... [and shaping] metal's definitive response to the 21st century."

In late 1985, Scott Kelly, Dave Edwardson, and Jason Roeder, formerly members of Violent Coercion, founded Neurosis as a hardcore punk outfit, inspired also by British crust punk in the vein of Amebix.

In 1986, Chad Salter was added on second guitar and vocals. There have only been a few changes in the lineup of Neurosis' musicians since band's inception. In 1989 guitarist/vocalist Chad Salter was replaced by Steve Von Till, who previously played in bands Transgressor, Peace Test and Tribe of Resistance, and in 1990, Simon McIlroy joined the band as a synthesizer/sampler with Adam Kendall as visual artist (Adam and Simon have been friends since they were teenagers and they were doing a lot of experimental music together before). In 1995, Noah Landis, a childhood friend of Dave Edwardson, replaced Simon McIlroy as keyboardist.

With The Word as Law, Neurosis began to transition from the rapid-fire hardcore punk of Pain of Mind to the more experimental sound of Souls at Zero, which featured slower tempos, unorthodox song structures, and guest performers on instruments like trumpet, violin and flute. The album would ultimately prove critical in the development of the post-metal genre and atmospheric sludge metal. Neurosis' signature sound came into full force with Enemy of the Sun, with The Quietus observing that "at the time few could have predicted this black hole of agonizingly precise metal riffs, unnerving backmasking, industrial folkisms and extensive sampling".

In 1996, Neurosis attracted mainstream attention with its Relapse Records debut, Through Silver in Blood and subsequent tour with Pantera. In 1999, Neurosis released Times of Grace, which was designed to be played synchronously with Grace, an album released by Neurosis' ambient side project, Tribes of Neurot.

In the early 2000s, the band founded their own independent record label, Neurot Recordings, which, in addition to releasing material from Neurosis and its associated projects, signed several other artists.