Ahn Jae-hyo was born in Busan, South Korea on December 23, 1990, where he lived with his parents and older brother.
Prior to his debut with Block B, Ahn was an ulzzang, and was featured in an Mnet television series focusing on male ulzzangs, 꽃미남 아롱사태, in 2007. He was a trainee for the boy band Beast, but was sidelined with an injury. He debuted with Block B in April 2011.
In early 2017, he became the first Korean pop idol to appear on the cover of Korean fishing magazine Fishing News. On March 18, 2018, Ahn appeared on the SBS television show It's Good To Be A Little Crazy and taught the actress Han Eun-jung how to fish.