Ōe was born in Ōse (大瀬村 Ōse-mura), a village now in Uchiko, Ehime Prefecture on Shikoku. He was the third son of seven children. Ōe's grandmother taught him art and oral performance. His grandmother died in 1944, and later that year, Ōe's father died in the Pacific War. Ōe's mother became his primary educator, buying him books such as The Adventures of Huckleberry Finn and The Wonderful Adventures of Nils, whose impact Ōe says "he will carry to the grave".
Ōe remembers his elementary school teacher claiming that Emperor Hirohito was a living god, and asking him every morning, "What would you do if the emperor commanded you to die?" Ōe always replied, "I would die, sir. I would cut open my belly and die." At home in bed at night he would acknowledge his reluctance to die and feel ashamed. After the war, he realized he had been taught lies and felt betrayed. This sense of betrayal later appeared in his writing.
Ōe attended high school in Matsuyama. At the age of 18, he made his first trip to Tokyo and in the following year began studying French Literature at Tokyo University under the direction of Professor Kazuo Watanabe, a specialist on François Rabelais. Oe began publishing stories in 1957, while still a student, strongly influenced by contemporary writing in France and the United States. He married in February 1960. His wife, Yukari, was the daughter of film director Mansaku Itami and sister of film director Juzo Itami. The same year he met Mao Zedong on a trip to China. He also went to Russia and Europe the following year, visiting Sartre in Paris.
In 1961, Ōe's novellas Seventeen and The Death of a Political Youth were published by a Japanese literary magazine. Both were inspired by seventeen-year-old Yamaguchi Otoya, who assassinated the chairman of Japan's Socialist Party in 1960, and then killed himself in prison three weeks later.
Yamaguchi had admirers among the extreme right wing who were angered by The Death of a Political Youth and both Ōe and the magazine received death threats day and night for weeks. The magazine soon apologized to offended readers, but Ōe did not. The story has never been reprinted or translated.
Ōe lives in Tokyo. He has three children; the eldest son, Hikari, has been brain-damaged since his birth in 1963, and his disability has been a recurring motif in Ōe's writings since.
In 1994 Ōe won the Nobel Prize in Literature and was named to receive Japan's Order of Culture. He refused the latter because it is bestowed by the Emperor. Ōe said, "I do not recognize any authority, any value, higher than democracy." Once again, he received threats.
Ōe at a 2013 antinuclear demonstration in Tokyo
In 2005, two retired Japanese military officers sued Ōe for libel for his 1970 essay, Okinawa Notes, in which he had written that members of the Japanese military had coerced masses of Okinawan civilians into committing suicide during the Allied invasion of the island in 1945. In March 2008, the Osaka District Court dismissed all charges against Ōe. In this ruling, Judge Toshimasa Fukami stated, "The military was deeply involved in the mass suicides". In a news conference following the trial, Ōe said, "The judge accurately read my writing."
Ōe has been involved with pacifist and anti-nuclear campaigns and has written books regarding the atomic bombings of Hiroshima and Nagasaki and the Hibakusha. Following the 2011 Fukushima nuclear disaster, he urged Prime Minister Yoshihiko Noda to "halt plans to restart nuclear power plants and instead abandon nuclear energy". Ōe has said Japan has an "ethical responsibility" to abandon nuclear power in the aftermath of the Fukushima nuclear disaster, just as it renounced war under its postwar Constitution. He has called for "an immediate end to nuclear power generation and warned that Japan would suffer another nuclear catastrophe if it tries to resume nuclear power plant operations". In 2013, he organized a mass demonstration in Tokyo against nuclear power. Ōe has also criticized moves to amend Article 9 of the Constitution, which forever renounces war.