In 1921 Polish population of the town of Třinec (Trzyniec) founded KS Siła Trzyniec, ethnically Polish sport club. In the same year local German population founded DSV Trzynietz. Two years later Czechs founded their own club SK Třinec. After the communist coup d'état of 1948, communists began to curb the number of organizations in Czechoslovakia and the Polish club was fused to the Czech one in 1952. The club played in the Czechoslovak First League for the first time in the 1963–64 season and returned to play three consecutive seasons there between 1970–71 and 1972–73. Two more seasons in the top flight followed in 1974–75 and 1975–76 before the club was relegated from the top flight.
After the dissolution of Czechoslovakia, the club regularly took part in the Czech 2. Liga. An eight year spell there was followed by five years in the third-tier Moravian–Silesian Football League, before a return to the Second Division came in 2006. Another stint in the Second Division followed, this time lasting for six years until relegation in 2012. The club won the Moravian–Silesian Football League in the 2012–13 season.
Their current home ground is Stadion Rudolfa Labaje, named after former famous local Polish footballer, Rudolf Łabaj. The stadium has a capacity of just over 2000. The club previously played at Lesní stadion, which is now mainly used for athletics.