Born in the town of Aso (today, Namekata, Ibaraki prefecture), Shizu was the eldest daughter of Satô Takanaka; when her father was adopted by Satô Taizen and succeeded him as head of the Juntendô medical school in 1859, she joined Takanaka in moving to Sakura (in Shimousa province, today, Chiba prefecture). In 1867, she married Satô Susumu, who was thus adopted into the family.
Shizu was educated in a variety of subjects, including kangaku (Chinese Studies), traditional Japanese subjects, and women's subjects, as well as naginata, Zen meditation, and poetry composition, and became fairly active in the local high society in Sakura.
In 1902, Shizu became a chief teacher, and later the principal, at a Girls' Art School founded in 1900 by Yokoi Tamako. She was awarded the Grand Cordon of the Order (kun rokutô hôkan shô) in 1915 for her contributions to women's education, alongside Tsuda Umeko and others.