Niilo Rudolf Tammisalo (originally Ekbom; 15 October 1894 - 5 February 1982) was an influential figure in Finnish sports in the first half of the 20th century.

When his career as a player came to a close in the early 1930s, he dedicated himself to coaching, refereeing, teaching, and administrating sports organizations.

Tammisalo played as goalkeeper at the semi-professional level with Helsingin Jalkapalloklubi (HJK) (Helsinki Football Club).

He began playing on the club's representative team in 1911, when he was 17 years old, and would remain loyal to HJK throughout his sixteen-season football career, helping them achieve seven Finnish Championship Cup victories (1911, 1912, 1917, 1918, 1919, 1923 and 1925).

The national team's match against the Swedish club IFK Uppsala resulted in a 4-1 victory that was described in the press as “one of the most amazing achievements of Finnish athletes.” [4] Tammisalo is credited with one appearance representing Finland in international ice hockey competition, a three-game series of friendlies against the Swedish national team that were played in Stockholm in February 1933.