Tuomo Oskari Suomalainen (born November 29, 1931 in Hogland, Finland died November 1, 1988) was a Finnish architect. He worked very closely with his brother Timo Suomalainen who also was an architect. Most of the works they designed jointly.
Their most well known work is Temppeliaukio Church in Helsinki, which has become one of the most visited sites in Finland. Tuomo Suomalainen's last work was the chapel at Kellonummi cemetery in Espoo, this too, together with his brother. The chapel was inaugurated in 1993.