First stop Appiah in Europe was Udinese Calcio in Italy. In the summer of 2000 he moved for the equivalent of 700,000 euros for AC Parma. After two average years followed in 2002 by the move to Brescia Calcio. But here Appiah did not stay long, because at the beginning of the season 2003/ 04 brought him Juventus for eight million euros. In the season 2005/ 06 Appiah joined the Turkish Süper Lig for Fenerbahçe Istanbul, the amount of the transfer fee also amounted to eight million euros. There he signed a four year contract with an option for another year. His first game for Fenerbahçe, he played on 5 August 2005 against Gençlerbirliği Ankara. Because of a complicated breach his contract was finally exposed to the end of the 2007/08 season. Then he kept fit with his former club Brescia Calcio. In November 2009, the hitherto without clubs Ghanaian international was signed from FC Bologna, where he, however, in the course of the season was only used twice. At the end of the season 2009/10, his contract was not renewed. In August 2010, Appiah signed a contract with the Serie A newly promoted Cesena, which ended at the end of the season 2010/11. After almost 8 months of Vereinslosigkeit Appiah was taken early February 2012, the Serbian first division side FK Vojvodina Novi Sad until the end of the season under contract.
His first cap for Ghana Stephen Appiah played in 1996 against the national team of Benin. In Ghana's squad for the 2006 World Cup in Germany thus the midfielder and captain was one of the most experienced and most important players. With the Black Stars, he reached the second round at that tournament. In 2006 he was elected to Ghana's Footballer of the Year.
In the 2010 World Cup in South Africa, he reached with his team the quarter-finals, Appiah was there, however, only a substitute.
After the World Cup, he announced that he will withdraw from the national team.
- U- 17 World Cup 1995 Ghana
- Ghanaian Champion 1997 with Hearts of Oak SC
- Ghanaian Cup Winners' Cup in 1996 with Hearts of Oak SC
- Italian Cup Winners' Cup in 2002 with Parma
- Italian champion in 2005 with Juventus (which was later withdrawn because of the manipulation scandal )
- Turkish champions Fenerbahce 2007