Kōno was born in Matsuyama, Ehime Prefecture’s capital city, on 7 August 1902. She enjoyed playing gateball as a nonagenarian, and kept a daily diary until this time.
Following the death of 112-year-old Takeno Fujita on 3 August 2012, Kōno became Ehime Prefecture’s oldest resident. She attained supercentenarian status four days later, and, in April 2015, surpassed Fujita’s age to become the oldest person ever in the prefecture.
Kōno died in Shimoidai, Matsuyama City on 24 April 2015 at the age of 112 years, 260 days. She was succeeded as the oldest living person in Ehime by Osugi Sogo, then aged 109, who went on to break Kōno’s age record for the prefecture in 2018.