Sou Fujimoto (藤本 壮介, Fujimoto Sōsuke, born 1971) is a Japanese architect.
Born in Hokkaido in 1971, he graduated from the University of Tokyo in 1994, and established his own office, Sou Fujimoto Architects, in 2000. Noted for delicate light structures and permeable enclosures, Fujimoto designed several houses, and in 2013, was selected to design the temporary Serpentine Gallery pavilion in London.
Fujimoto published a book in 2008 called Sou Fujimoto: Primitive Future. It contains an overview of his projects up to that date, and it explains his concept of primitive future and how he uses it in his work.
After establishing Sou Fujimoto Architects in 2000, Fujimoto went on to design buildings across Japan and Europe. Many of his designs are built around his idea that the function of a building is decided by human behavior.
In 2019, Fujimoto was selected as one of 23 architects to "reinvent" Paris. His contributions to this project include a redesign of a plot in the 17th arrondissement of Paris.