"Sayonara wa Emotion" (Japanese: さよならはエモーション, Hepburn: Sayonara wa Emōshon^?, "Goodbyes Are Emotion") (Japanese pronunciation: [sajonaɺawa.e:mo:ɕon]) is a song by Japanese band Sakanaction. Initially used as a 2013 jingle for the yobikō Tōshin High School, the song was recorded in full a year later. It was released on October 29, 2014, as a double A-side single with the song "Hasu no Hana".

Sakanaction's singles for their album Documentaly (2011), "Identity" (2010), "Rookie" (2011) and "Bach no Senritsu o Yoru ni Kiita Sei Desu" (2011), were featured in commercials for the yobikō Tōshin High School. The commercials utilized songs Sakanaction had personally wanted to release as singles, and were not written expressly for the commercials. This was unlike "Yoru no Odoriko" (2012), a single by the band which had been specifically commissioned by Mode Gakuen for a commercial.

In March 2013, Sakanaction released their sixth studio album Sakanaction. The album was a result of the band's vocalist and songwriter Ichiro Yamaguchi feeling a new resolution to create music that would resonate with a general pop music audience. The album debuted at number one on Oricon's weekly albums chart, after selling 83,000 copies. This was a record for the band, both in terms of the number of copies that they had sold in one week of a release, as well as the fact that they had never reached number one on an Oricon chart before. The release is currently the band's most successful album, in terms of physical copies sold.

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