He graduated from Political Science Department of Tokyo University in 1910. He visited Europe for one year studying educational system (1921-1922).
Juichi Shimomura served successively as director and as rijikan (commissioner) of Tokyo, school inspector, counselor of Education Ministry, private secretary to Education Minister and president of Tokyo Women's Higher Normal School and Joshi Gakushiiin (Peeresses' School).
Upon retirement from the government service assumed his post of Chairman of Shukyo Hojin Shingikai (Religious Judicial Persons' Council) (1946) and vice-chairman of Nihon Kodokai (Japan Society for Propagation of the Way of Self-Discipline). He held additional post of chief director of Joshi Shakai Kyoikukai (Women's Social Education Society).