Kimiko Ono was born in Wakayama City, Wakayama Prefecture, Japan on 20 June 1908. She was the second of seven siblings. She had one older brother, three younger brothers, and two younger sisters. She graduated from an elementary school in Wakayama City in March 1921. In November 1927, at the age of 19, she married Kitaro Ono [Japanese: 喜太郎]. The couple had four children (two sons and two daughters).

During World War II, Ono and her family were evacuated to Kokawa Town, Wakayama Prefecture (now Kinokawa City), where they lived until 1955. During that time, she worked growing crops. Her husband Kitaro died in 1962.

Ono moved to Osaka Prefecture at the age of 92. She lived with her children until the age of 107, when she moved into a nursing home in Sakai, Osaka. A keen traveler, she has traveled all over Japan from Hokkaido to Okinawa, and when she was 107, she stayed overnight at Arima Onsen in Hyogo Prefecture.

Ono has no foods she dislikes, and she especially likes to eat meat. She used to grate her vegetables herself to make and drink vegetable smoothies before blenders were in widespread use. She had good eyesight, and she was reading the small letters in her booklet with the naked eye until she was 113 years old. At the time of her 114th birthday in June 2022, she was able to move her wheelchair around the nursing home on her own.