Miki Imamura was born in Minamata, Kumamoto Prefecture, Japan, on 4 March 1904. Her family owned a long-established restaurant. She graduated from Oe Girls’ High School (present-day Kumamoto Face Gakuin High School). At the age of 20, she married Daiki Imamura, whom she met at a Protestant church in Minamata.

After marriage, the couple ran a haberdashery, selling daily necessities. However, her husband wanted to make use of her culinary talents, and the couple founded a Japanese confectionery shop when Miki was 29 years old. She trained under Japanese confectioner for three days, and continued her research on making red bean paste on her own, later succeeding in commercializing yōkan. Her product was a big hit, and the yōkan she made quickly became popular in the area.

Around 1970s, she developed a new product with her second son, and began selling it under the name “Miki Monaka” (she included her first name in the product’s name). The product remains a well-known confection loved in the city of Minamata.

At the age of 99, a part of her daily routine was waking up at 6 AM and reading Bible verses. She was a Christian, and her favorite saying was “faith is devotion.” She claimed the secret to her longevity was “to live faithfully according to the Scriptures” and to drink red wine in the evening.

Miki Imamura passed away in Minamata, Kumamoto Prefecture, Japan, on 6 November 2015, at the age of 111.