"Goodbye" (Chinese: 再見; pinyin: Zàijiàn) is a song by Chinese-Hong Kong singer-songwriter G.E.M., serving as the fifth single for her fourth studio album Heartbeat (2015).

It was released via digital download and streaming on October 30, 2015, by Hummingbird Music.

The music video for "Goodbye" was directed by Shane Drake, who had previously worked with artists such as Avril Lavigne, Paramore, and Fall Out Boy.

His search leads him to the rooftop, only to discover her absence, with a note reading "Goodbye" as the sole trace of her presence.

performed "Goodbye" at The 4th V Chart Awards at the Cadillac Arena in Beijing, China on April 4, 2016.