Motoi Fukunishi was born in the village of Soudou (present-day Shimotsuma), Ibaraki Prefecture, Japan, on 25 March 1910. When he was a junior high school student, he met American missionaries, Mr. and Mrs. Binfold, and became a member of the Shimotsuma Christian Friends group in 1927.

After graduating from Ibaraki Prefectural Shimotsuma Junior High School and then Ibaraki Prefectural Normal School, he was assigned as a teacher at Murata Vulgar Elementary School in Makabe County. He worked as a teacher for 39 years in total, serving as both an elementary and middle school principal for some time.

In 1988, he was awarded the Order of the Rising Sun, Gold Rays with Rosette. He was later said to be the oldest living recipient of the honor in Japan. After retiring, he took over as director of Shimotsuma Shoutomo Kindergarten in Shimotsuma City, where his wife had worked, and remained the principal until the age of 105. When asked about the secret of his longevity, he attributed it to spending time around children in kindergarten and never missing a walk. He loved sweet foods.

Motoi Fukunishi passed away in Shimotsuma, Ibaraki Prefecture, Japan, on 22 August 2020, at the age of 110 years, 150 days.