According to records, he was born on 19 April 1897[1] in the fishing village of Kamiukawa, in the Kyoto Prefecture of the Empire of Japan, to farmers Morizo (1858–1935) and Fusa (1867–1931) Miyake.

[7] After thorough research, including conducting family interviews and searching official records, the authors verified Kimura's age and date of birth.

[7] On 1 April 1918, Kimura was conscripted into the Imperial Japanese Army and was posted to Nakano, Tokyo, where he served with a communications unit.

To help support his younger brother A. M. who had emigrated to Korea under Japanese rule for work and had fallen ill there, Kimura moved to Keijō (now Seoul, South Korea), taking a job on 31 May with the Government-General of Chōsen in the Mail and Telecommunications Department, with a salary of 30 yen plus a 30% overseas service allowance.

[5][7] From 1 to 21 September 1921, Kimura underwent a final three-week period of army service, again in a communications unit, during which he was posted to Hiroshima.

Around this time, he attended a ceremony in Kyoto to welcome the return to Japan of Crown Prince Hirohito from a tour of Europe.

[7] After his national service, Kimura resumed farming until 21 April 1924, when he was appointed a deputy postmaster at the Hira post office.

He credited eating small portions of food (hara hachi bun me) as the key to a long and healthy life.

[14] On his 114th birthday on 19 April 2011, he mentioned his survival of the 7.6 magnitude 1927 Kita Tango earthquake that hit Kyoto and killed over 3,000 people.

[16] On his 116th and final birthday, Kimura received many well-wishes, including a video message from Japan's prime minister Shinzō Abe.

However, his health started worsening again in early June 2013, as his blood sugar level, urine production and response declined.

Kimura died of natural causes in a hospital in his hometown of Kyōtango, western Japan, at 2:08 a.m. on 12 June 2013,[19][20] and was succeeded as the world's oldest living man by Salustiano Sánchez (born 8 June 1901), and as the oldest living person by fellow Japanese citizen Misao Okawa of Osaka (who was 320 days younger).