Stylianos Giannakopoulous (popularly known as Stelios) (born July 12, 1974 in Athens, Greece) is a Greek football player who currently plays for Bolton Wanderers F.C. as a midfielder.

He initially started in his homeland of Greece, spending his first playing season with Ethnikos Asteras . Having been thrust immediately into first-team action, he found himself scoring six goals in his opening season, before moving to Paniliakos PANH , where, in the three years he spent there, he scored 26 goals in 84 games. Olympiacos CFP soon were after his signature.

However, after seven years playing in Greece, and having achieved such a high rating, he was snapped up by Bolton Wanderers. Having made his Bolton debut in a 4-0 defeat to Manchester United F.C., and, growing in confidence, he was one of the players selected for the Greece national football team which were victorious in the 2004 European Football Championship.