Yi has written novels, short stories, and Korean adaptations of classic Chinese novels, as well as political and social commentaries. In 2014, he stated "I have written 50 short stories and novellas in six volumes, 18 novels in 20 volumes, and two epic novels in 22 volumes. In addition, I have written two volumes of essays, one travelogue, and compiled and annotated a total of 20 volumes of Chinese classics, as well as 10 volumes of short and medium-length masterpieces of world literature."