[1]) is a South Korean boy band formed by Beat Interactive, and co-managed with Swing Entertainment.

The group consists of five members: Park Jun-hee, Lee Dong-hun, Wow, Kim Byeong-kwan, and Kang Yu-chan.

A.C.E first gained a following busking on the streets of the hip Hongdae district in Seoul, covering the dance choreography of popular groups.

Donghun competed on Superstar K5 prior to becoming a trainee under CJ E&M, and later appeared on I Can See Your Voice as well, winning the episode and earning high praise from Got7's JB.

Wow trained at YG Entertainment alongside Winner[3] before later moving to CJ E&M, where he met Jun and Donghun.

[3] Kim Byeong-kwan participated in the first season of K-pop Star but was eliminated during the final round of casting.

On March 15, 2018, the group released a special single titled "5TAR (Incompletion)", with the song serving as a gift to fans after their brief hiatus to join The Unit and Mix Nine.

[12] A.C.E featured on their first collaboration with French DJ Hcue for the track "I Feel So Lucky" released on September 14, 2018, aiming for a Moombahton sound fused with K-pop elements.

[15] A.C.E released their fourth extended play HJZM: The Butterfly Phantasy on September 2, 2020 with the title track "Favorite Boys".

[17] A.C.E released a remix titled "Fav Boyz" on January 8, 2021 of their song "Favorite Boys" by American DJ Steve Aoki, featuring the Nigerian-American rapper Thutmose.

The countries where it reached Number 1 include (but are not limited to): Brazil, Belarus, Ecuador, Peru, Norway, Indonesia, Russia, Singapore, Portugal and Malaysia.

[24] The EP earned many strong reviews with NME praising the members, stating: “Keep an eye on this headstrong quintet, because there's no question they'll surprise us in the years to come.”[25] A.C.E released "Spark" as part of the original soundtrack for boys' love Korean drama Light on Me on July 8, 2021.

Their album release project, titled "PetFlix", included the opening of an official website designed with an OTT site concept.

[45][46] The project also featured a 5 member busking event (including Yuchan, who returned from enlistment the day prior) on February 16 at COEX Mall before the release.

It also ranked 63rd in the Media Base Top 40 music chart following BTS, Blackpink, NewJeans, TXT, and Monsta X.