[1] Yokoi was born in 1924 in Nagoya, Aichi, and soon after moved to Tsushima, Japan.

[1] As a child, she studied under Kouki Suzuki, a member of Shunyo-kai art society.

She has exhibitioned at the California Palace of the Legion of Honor, the Seibu Art Forum, and the Galerie Kornfeld in Bern, among others.

In November 2004, the Teruko Yokoi Hinagashi Museum was founded in Ena, Gifu,[3] and in 2008, the Yokoi Teruko Fuji Museum of Art was founded in Fuji, Shizuoka.

[4] In 2014, at age 90, Yokoi created works for a benefit exhibition, with the proceeds from the paintings going to UNESCO Biosphere Entlebuch.