Im Joo-eun made her acting debut in the 2005 film Wuthering Heights. In 2009, she starred in the MBC horror-thriller Hon, which won her Best New Actress at the MBC Drama Awards. In 2011, she acted alongside Im Joo-hwan and Daesung in the MBN musical drama What’s Up. In 2013, she portrayed a teacher in the SBS series Heirs, which bagged the Outstanding Korean Drama citation at the 9th Seoul International Drama Awards. In 2014, she played a supporting role in the hit MBC sageuk Empress Ki. In 2016, she joined the main cast of the KBS2 series Uncontrollably Fond, which was followed by another main role in the 2017 MBC drama Thief-nom, Thief-nim. In 2020, she was cast in a supporting role in the top-rating Channel A suspense melodrama Lies of Lies.

Im Joo-eun attended the Dongduk Women’s University in Seoul.