Yoshiyuki was born in Okayama, the oldest child of author Yoshiyuki Eisuke, but his family moved to Tokyo when he was 3. He attended Shizuoka High School, where he grew interested in Thomas Mann's stories, and in 1945 entered the University of Tokyo. He left the university without a degree and began working fulltime as an editor at a weekly scandal magazine, while spending much of his leisure time gambling, drinking, and frequenting prostitutes. Sexuality and prostitution would form a consistent theme in his writing.
Yoshiyuki's first published fiction was Bara Hanbainin (?????, The Rose Seller, 1950), followed by the novels Genshoku no Machi (The City of Primary Colors, 1951, revised 1956), Shu-u (??, Sudden Shower, 1954), for which he won the Akutagawa Prize, and Shofu no Heya (Room of a Whore, 1958). His novel Anshitsu (??, The Dark Room, 1969) won the Tanizaki Prize. Another of his most celebrated works, Yugure Made (?????, Until Evening, 1978), took 13 years to write but once published quickly became a best-seller and won the Noma Literary Prize.