Lee Dong Yeol

On September 6, 2015, Xiao's teaser photos for UP10TION's then upcoming debut was released. On September 10, he then debuted as a member of UP10TION with their debut mini album Top Secret. He appeared as a contestant on Mnet's reality survival show Boys Planet.

On March 23, he was eliminated in episode 8 after ranking 44th place. On March 31, it was announced that his contract with TOP Media had concluded. On July 20, a source from PA Entertainment announced that Xiao has signed with them and would continue to promote in diverse fields in both Korea and overseas under his real name.