"Nightrain" is a song by the American rock band Guns N' Roses. It is the third song on the band's debut studio album, Appetite for Destruction (1987). Although it was released as a single, the song was not included in their best-of album. It reached #93 on the US Billboard charts. The song is a tribute to an infamous brand of cheap Californian fortified wine, Night Train Express, which was extremely popular with the band during their early days because of its low price and high alcohol content. The title is spelled differently, omitting one of the 'T's between "Night" and "Train", and removing the space, making a single portmanteau of the two words. The song was ranked eighth on Guitar World's list of the "Top 10 Drinking Songs."

Slash describes "Nightrain" as "an anthem that we came up with on the spot". The original idea for the song came when Slash and Izzy Stradlin wrote the main riff while they were sitting on the floor of the band's practice room. The next day, Slash was ill so Stradlin finished writing the music with Duff McKagan. However they did not write any lyrics. The song remained incomplete until one night when the band was walking down Palm Avenue sharing a bottle of Night Train. Someone yelled 'I'm on the night train!' and the whole band joined in, with Axl Rose improvising the lines in between: "Bottoms up!" "Fill my cup!" etc. "Nightrain" was born. After this initial inspiration, the band finished the song within a day. According to the autobiography of Paul Stanley from Kiss, the pre-chorus of the song used to be the actual chorus until Rose let Stanley hear a demo of the song and advised Rose to use the chorus as the pre-chorus.

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