Konstantinos "Kostas" Triantafyllopoulos (Greek: Κωνσταντίνος "Κώστας" Τριανταφυλλόπουλος; born 3 April 1993) is a Greek professional footballer who plays as a centre-back for Super League club Asteras Tripolis.

[2] On 30 September 2012, during a Superleague match vs. Asteras Tripolis, Triantafyllopoulos made his debut for Panathinaikos.

At the end of the season, Triantafyllopoulos signed a contract extension for three years.

On 20 May 2021, Pogoń announced the renewal of the 28-year-old Greek defender's contract for one year with the possibility of extending their cooperation for another season.

[8] On 19 July 2023, Triantafyllopoulos moved on a free transfer to another Ekstraklasa club Górnik Zabrze, with whom he signed a two-year contract.