Reino Nyyssönen (12 February 1935 – January 2023) was a Finnish tennis player.

[1] Nyyssönen was a native of Turku but it was in Sweden that he took up the sport of tennis, after coming to the country as a World War II child evacuee.

When he returned to Finland he continued his tennis development in Kotka.

[2] A Davis Cup player for Finland from 1955 to 1964, Nyyssönen won a total of 35 national championships, including six indoor and seven outdoor singles titles.

Amongst his best grand slam performances, he made the mixed doubles quarter-finals at the 1961 Wimbledon Championships and the singles fourth round at the 1962 U.S. National Championships.