In December 2011, Lee auditioned for SBS reality survival program K-pop Star, where she finished as runner-up behind Park Ji-min.

On December 31, Lee appeared on MBC's Infinite Challenge Hip-hop & History special as a featured guest for Yoo Jae-suk and Dok2's stage.

[21] On August 20, Lee appeared on SBS' Party People where she shared she suffered from minor panic attacks in the past, thus the creation of her 2016 hit single "Breathe".

On March 21, 2018, Lee's Japanese debut album was released, thus embarking on her Japan tour at stops including Tokyo and Osaka.

[24] On January 15, 2019, Lee released digital single "XI" with Code Kunst, the track was sung live for the first time on MBC Dreaming Radio.

[31] In June 2020, Lee joined as a cast member for the fourth installment of JTBC show Begin Again from episode 4 to 6.

[32] On July 22, 2020, AOMG revealed that they had signed an exclusive contract with Lee Hi and released her comeback single "Holo.

"[33] "Holo" peaked at number 7 on the Gaon Digital Chart and won R&B Track of the Year at the Korean Hip-hop Awards.

In addition, a video content of her unreleased new song "One Thing" was released on her YouTube channel to celebrate her 28th birthday.

[40][41] On July 28, Lee held a fan sign with MAC at Lotte World Mall, Seoul, South Korea.

On October 15, in collaboration with MAC and magazine Marie Claire, Lee held an event showcasing stages of her songs as well as covers of other artists.