In December 1928, whilst a student at Tokyo's Fine Arts College, Yoshimura began part-time work at Antonin Raymond's office, becoming full-time after he graduated in 1931. Amongst many works he did on-site supervision of the Akaboshi Cottage (1931) for Japanese golfer Shiro Akaboshi, a house for Kisuke Akaboshi (1932) and the Kawasaki House (1934).
In May 1940 he travelled to Antonin's home in New Hope, Pennsylvania, spending fourteen months living and working in the studio there. He oversaw the installation of a small tea house at the Japan Institute in New York City.
On his return to Tokyo in 1941 he set up his own practice. In 1953, because of his connections with Raymond, Yoshimura secured the project to design a traditional Japanese Tea House in the garden of the Museum of Modern Art in New York. This house, named Shofuso, or Pine Breeze Villa, was moved to Philadelphia, PA in 1957, where it remains as a historic site open to the public as Shofuso Japanese House and Garden.
In 1955 he collaborated with Kunio Maekawa and Junzo Sakakura to design the International House of Japan in Roppongi, Tokyo. This cultural exchange complex is located within estates owned by samurai lords in the Edo period. It is constructed in-situ thin-set reinforced concrete walls, pre-cast concrete columns and beams and Oya Stone.
Yoshimura's later works include the Tikotin Museum of Japanese Art (1959) in Haifa, Tokyo Imperial Palace (1968), Japan House (with George G. Shimamoto of Kelly & Gruzen, 1969–71) in New York City, the East and West Wings of the Nara National Museum (1972) and the Royal Norwegian Embassy (1977) in Tokyo.
With his colleagues, he won the Prize of the Architectural Institute of Japan for Specific Contribution for the International House of Japan.
- Helfrich & Whitaker (2006) p269
- Stewart (2002) p134-142
- Helfrich & Whitaker (2006) p272
- Helfrich & Whitaker (2006) p59
- Japan Architect p72
- Tokyo Imperial Palace, Works by Major Architects: Japanese Architects (accessed April 24, 2008); Norwegian Embassy, Exhibition of Junzo Yoshimura - the architect for the Norwegian Embassy, Tokyo (Norway's official site in Japan, accessed April 24, 2008); Tikotin Museum of Japanese Art, The Tikotin Museum of Japanese Art (retrieved April 24, 2008); Japan Society, Japan Society, New York - Circle of Friends (retrieved April 24, 2008); International House of Japan, About IHJ (retrieved April 24, 2008; Nara National Museum, East Wing and West Wing (both accessed April 24, 2008).
- 日本建築学会各賞受賞者・受賞業績検索 （姓：吉村；名：吉村） Retrieved April 24, 2008
- Helfrich & Whittaker, Kurt & William (2006). Crafting a Modern World, The Architecture and Design of Antonin and Noemi Raymond. Princeton Architectural Press.
- Stewart, David B (2002). The Making of a Modern Japanese Architecture, From the Founders to Shinohara and Isozaki. Kodansha International.
- Spring 2005, "Do_co,mo.mo Japan: the 100 selection", The Japan Architect, No57