"Smells Like Teen Spirit" is a song by the American rock band Nirvana. It is the opening track and lead single from the band's second album Nevermind (1991). Written by Kurt Cobain, Krist Novoselic, and Dave Grohl and produced by Butch Vig, the song uses a verse-chorus form where the main four-chord riff is used during the intro and chorus to create an alternating loud and quiet dynamic.

The unexpected success of "Smells Like Teen Spirit" propelled Nevermind to the top of the charts at the start of 1992, often marked as the point where alternative rock entered the mainstream. "Smells Like Teen Spirit" was Nirvana's first and biggest hit, reaching number six on the Billboard Hot 100 and placing high on music industry charts all around the world in 1991 and 1992.

"Smells Like Teen Spirit" received many critical plaudits, including topping the Village Voice Pazz & Jop critics' poll and winning two MTV Video Music Awards for its music video, which was in heavy rotation on music television. The song was dubbed an "anthem for apathetic kids" of Generation X, but the band grew uncomfortable with the success and attention it received as a result. In the years since Cobain's death, listeners and critics have continued to praise "Smells Like Teen Spirit" as one of the greatest rock songs of all time.