Kim Tong-ni (real name: Kim Sijong) was born on 24 November 1913, in Gyeongju, Gyeongsangbuk-do, Korea. Kim attended Gyeseong Middle School in Daegu before transferring to Kyungshin Middle School in Seoul. After family circumstances forced him to drop out, he devoted himself to reading in place of regular coursework. He read a tremendous number of books, including philosophy, world literature and Eastern classics. In fact, Kim's eldest brother Kim Beom-bu, who was a scholar of Chinese classics and a philosopher, had great influence on his extensive reading and his prospects of becoming a writer of Korean literature.

Kim was so poor from his childhood that hunger was almost part of his life. He once wrote that sometimes if there was any liquor remaining in the bowl after his father drank from it, he would gulp down even that leftover liquor to relieve his hunger. In 1928, he dropped out of school in order to devote himself to writing. He started his literary career by publishing poems in various newspapers at the age of 16. He made a name for himself in the Korean literary world with his short stories. Over the years he received numerous literary awards. Kim Dongri debuted as a poet in 1934 with the publication of the poem "White Heron" (Baengno) in the Chosun Ilbo and emerged as a fiction writer the next year when his story "A Descendant of Hwarang" (Hwarangui huye) was published in the JoongAng Ilbo.

He was also active in a number of organizations such as The Association of Young Korean Writers (Hanguk cheongnyeon munhakga hyeophoe), The Korea Academy of Arts (Daehanminguk yesurwon), and the Korean Writers' Association (Hanguk munin hyeophoe).

Kim was married to the writer Son So-hui (1917-1987). Kim died on 17 June 1995.