Lee Jiham, formerly known as Lee Donghun and Donghun, is a South Korean singer under Beat Interactive. He is the main vocalist of the boy group A.C.E.

In 2017, Lee Donghun, and his fellow members Kim Byeongkwan and Wow, became contestants on the JTBC's new survival show MIXNINE. He made it to the final lineup after achieving 8th place, but unfortunately, after much discussion, it was decided the MIXNINE group would not debut.

As of August 12, 2023, A.C.E member Lee Donghun began using his given name, Lee Donghun, for promotions, transitioning from his previous stage name, Donghun. Recently, on February 27, 2025, he announced a further change to Lee Jiham, stating, "I've decided to live my life as easy-ham (pronounced like Lee Jiham)."