Gugudan 5959 was a south-korean subunit group of Gugudan formed by Jellyfish Entertainment in 2017. The "5959" in their name was made up of their represented numbers in Gugudan: Hyeyeon representing the number 5 and Mina representing the number 9. After Hyeyeon left the main group in October 2018, the sub-unit became inactive. The only single was the debut single "Ice Chu" in 2017.