Haruko Mekaru was born in Nanjō City, Okinawa Prefecture, Japan, on 5 July 1910. At some point, she got married, and her husband was a skilled master carpenter. During the Pacific War, Nanjo City (then Tamaki Village), where she and her family resided, became the site of a fierce battle. However, they managed to avoid the devastating effects of the war because they lived far from the main road. Her entire family safely endured the challenges of the war.

In December 2006, she made a donation to a local welfare organization in commemoration of her Kajimayā (her 97th birthday). At some point, she moved into a nursing home for the elderly. Mekaru celebrated her 111th and 112th birthdays at the nursing home, dressed in her kimono, and enjoyed sata andagi, an Okinawan sweet deep-fried bun similar to a doughnut, with the company of staff and fellow residents. Her son, a shamisen craftsman, said that the secret to Mekaru’s longevity was “not getting angry.” Even when strangers came to visit, she took pleasure in serving them tea and sweets, entertaining them with hospitality. She was renowned as a virtuous individual who found joy in extending warmth to others.

Haruko Mekaru passed away at her nursing home in Nanjō City, Okinawa Prefecture, Japan, on 21 November 2022, at the age of 112 years, 139 days.