"Gashina" is a song recorded by South Korean singer Sunmi. It was released as a CD single and digital single by Makeus Entertainment and The Black Label on August 22, 2017, and distributed by LOEN Entertainment. "Gashina" is Sunmi's first release since the disbandment of Wonder Girls and the expiration of her contract with JYP Entertainment. It was released as the lead single from her second Korean-language EP Warning.

Lee Sun-mi, known mononymously as Sunmi, is a South Korean singer, dancer, songwriter and record producer. She debuted in 2007 as a member of South Korean girl group Wonder Girls and left the group in 2010 to pursue her studies. After a three-year hiatus, Sunmi resumed her career as a soloist with her 2013 debut extended play, Full Moon, spawning the number two singles "24 Hours" and "Full Moon" on the national Gaon Digital Chart.