Kiss (commonly styled in all caps) was an American rock band formed in New York City in 1973 by Paul Stanley (vocals, rhythm guitar), Gene Simmons (vocals, bass guitar), Ace Frehley (lead guitar, vocals) and Peter Criss (drums, vocals). Known for their face paint and stage outfits, the group rose to prominence in the mid-1970s with shock rock–style live performances that featured fire-breathing, blood-spitting, smoking guitars, shooting rockets, levitating drum kits and pyrotechnics. The band went through several lineup changes, with Stanley and Simmons remaining the only consistent members. The final lineup consisted of Stanley, Simmons, Tommy Thayer (lead guitar, vocals) and Eric Singer (drums, vocals).

With their makeup and costumes, the band members took on the personas of comic book-style characters: the Starchild (Stanley), the Demon (Simmons), the Spaceman or Space Ace (Frehley), and the Catman (Criss). During the second half of the 1970s, Kiss became one of America's most successful rock bands and a pop culture phenomenon. The band's commercial success declined during the early 1980s; however, it experienced a resurgence in 1983 when the band members began performing without makeup and costumes, marking the beginning of the band's "unmasked" era that would last until 1996. The first album of this era, 1983's platinum-certified Lick It Up, successfully introduced the band to a new generation of fans, and its music videos received regular airplay on MTV. In response to a wave of Kiss nostalgia in the mid-1990s, the original lineup reunited in 1996; at this time, the band resumed using makeup and stage costumes. The resulting 1996–1997 reunion tour was the band's most successful, grossing $143.7 million. In January 2019, Kiss began its final worldwide tour, and the band retired after performing its final show in New York City in December 2023.

Kiss is regarded as one of the most influential rock bands of all time, as well as one of the best selling bands of all time. Kiss has also earned 30 Gold albums, the most of any band from the United States. Kiss has earned 14 Platinum albums, three of which earned multi-Platinum status. The four original members of Kiss (Simmons, Stanley, Criss, and Frehley) were inducted into the Rock and Roll Hall of Fame in April 2014. Kiss was ranked by MTV as the ninth-greatest metal band of all time, placed tenth on VH1's "100 Greatest Artists of Hard Rock" list, was ranked as the third "Best Metal and Hard Rock Live Band of All Time" by Loudwire magazine, and was placed sixteenth by the British magazine Classic Rock on their "The 50 Best Rock Bands of All Time" list.

Kiss traces its roots to Wicked Lester, a New York City–based rock band led by Gene Simmons and Paul Stanley. That band recorded one album, which was shelved by Epic Records, and played a handful of live shows. Simmons and Stanley, feeling a new musical direction was needed, abandoned Wicked Lester in 1972 and began forming a new group.

Kiss was formed in 1973. After breaking up Wicked Lester late in 1972, Simmons and Stanley came across an ad in the East Coast version of Rolling Stone placed by Peter Criss, a drummer from the New York City scene who had previously played in the bands Lips and Chelsea. Simmons and Stanley met Criss in a nightclub where he was playing drums. After hearing Criss sing, they thought Criss should be in the new band they were forming. Criss then auditioned for, and later joined their new band. The three focused on a much harder style of rock than that played by Wicked Lester. In November 1972, the band played a showcase for Epic Records A&R director Don Ellis, in an effort to secure a record deal. In early January 1973, the group added lead guitarist Ace Frehley. Frehley impressed the group with his first audition, and was asked back for a second audition. A few weeks after Frehley joined, the classic lineup was solidified as the band to be named Kiss. They also began experimenting with their image, by wearing makeup and various outfits.

Stanley came up with the name while he, Simmons, and Criss were driving around New York City. Criss mentioned that he had been in a band called Lips, so Stanley said something to the effect of "What about Kiss?" Frehley created the now-iconic logo, making the "SS" look like lightning bolts, when he went to write the new band name over "Wicked Lester" on a poster outside the club where they were going to play. (Some of Wicked Lester's artwork included one lightning bolt for the "S" in Lester.) Later, Stanley designed the logo with a Sharpie and a ruler and accidentally drew the two S's nonparallel because he did it "by eye". The art department asked him if he wanted it to be redrafted to be perfect and he said, "It got us this far, let's leave well enough alone. Our number one rule has always been no rules."

The letters happened to look similar to the insignia of the Nazi SS, a symbol that is outlawed in Germany by Section 86a of the German criminal code. However, Simmons and Stanley, both Jewish, have denied any intentional likeness to Nazi symbolism in the logo. Since 1980, most of the band's album covers and merchandise in Germany have used a different logo, in which the letters "SS" look like the letters "ZZ" backwards. This logo is also used in Austria, Switzerland, Lithuania, and Hungary to avoid controversy.

The band's name has repeatedly been the subject of rumors pertaining to alleged hidden meanings. Among these rumors are theories that the name is an acronym for "Knights in Satan's Service", "Kinder SS", or "Kids in Satan's Service". Simmons has denied all of these claims.