Ryūnosuke Akutagawa (芥川 龍之介 Akutagawa Ryūnosuke?, 1 March 1892 – 24 July 1927) was a Japanese writer active in the Taishō period in Japan. He is regarded as the "Father of the Japanese short story" and Japan's premier literary award, the Akutagawa Prize, is named after him. He committed suicide at the age of 35 through an overdose of barbital.

Ryūnosuke Akutagawa was born in the Kyōbashi district of Tokyo, the third child and only son of father Toshizō Niihara and mother Fuku Niihara (née Akutagawa). He was named "Ryūnosuke" ("Son [of] Dragon") because he was born in the Year of the Dragon, in the Month of the Dragon, on the Day of the Dragon, and at the Hour of the Dragon. His mother went insane shortly after his birth, so he was adopted and raised by his maternal uncle, Akutagawa Dōshō, from whom he received the Akutagawa family name. He was interested in classical Chinese literature from an early age, as well as the works of Mori Ōgai and Natsume Sōseki.

He entered the First High School in 1910, developing relationships with classmates such as Kan Kikuchi, Kume Masao, Yamamoto Yūzō, and Tsuchiya Bunmei, all of whom would later become authors. He began writing after entering Tokyo Imperial University in 1913, where he studied English literature.

While still a student he proposed marriage to a childhood friend, Yayoi Yoshida, but his adoptive family did not approve the union. In 1916 he became engaged to Fumi Tsukamoto, whom he married in 1918. They had three children: Hiroshi Akutagawa (1920–1981) was an actor, Takashi Akutagawa (1922–1945) was killed as a student draftee in Burma, and Yasushi Akutagawa (1925–1989) was a composer. After graduation, he taught briefly at the Naval Engineering School in Yokosuka, Kanagawa as an English language instructor, before deciding to devote his full efforts to writing.