Siim Troost (born 7 December 1999) is an Estonian tennis player.

Troost has a career high ATP singles ranking of 1374, achieved on 18 July 2022.

Troost represents Estonia at the Davis Cup, where he has a W/L record of 4–2.

[1] Troost currently plays college tennis at Vanderbilt University.

This biographical article relating to Estonian tennis is a stub.