2AM (투에이엠) is a South Korean group, that consisted of Jo Kwon, Lee Changmin, Lim Seulong and Jeong Jinwoon.

The group debuted with “이 노래 (This Song)” in July 2008, under JYP Entertainment. It was one of the two subgroups split from the eleven-member boy band One Day, the other being 2PM.

In 2010, they were signed under a joint management contract with BigHit Entertainment, and released their first full-length album, Saint o'Clock.

Since 2015 the group stayed on hiatus, as their joint contact with BigHit expired and members didn’t decide to extend their contracts with only JYP, as well as they enlisted for their mandatory military service.

In 2021, 2AM announced the group reunion and comeback with an album Ballad 21 F/W, under Stone Music Entertainment.