DIA (다이아; short for Diamond, also known as Do It Amazing) is a nine-member girl group under MBK Entertainment. They debuted on September 14, 2015 with the album Do It Amazing.
On April 5, 2017 it was announced that Jooeun and Somyi were added as new members to the group.
- Eunice (유니스) - main vocals, lead dance, leader
- Jooeun (주은) - main vocals
- Heehyun (희현) (Cathy (캐시)) - main rap, lead dance, sub vocals
- Jenny (제니) - sub vocals, visuals
- Yebin (예빈) - lead vocals
- Eunjin (은진) - main dance, lead rap, sub vocals
- Chaeyeon (채연) - visuals, sub vocals
- Eunchae (은채) - lead vocals
- Somyi (솜이) - lead vocals, maknae
- Seunghee (승희) - main vocals, leader
- "My Friend's Boyfriend" (2015)
- Through a poll voted by the fans, it was determined a fan of the group would be called an "AID."