Ivanschitz began his football career as a youth in his town's local team called ASK Baumgarten, where he spent nine years.
Soon, Rapid Wien scouters found out about his talent and in 1998, he signed his first professional contract with the Austrian champions. He was only 16 years old when he wore his team's shirt during an Austrian Cup match against Ranshofen on 26 October 1999. His first official League match was in 2000 against Wüstenrot Salzburg. In 177 games for Rapid Wien, Ivanschitz scored 27 times, winning the Austrian Championship title in 2004–05. In 2003, he was elected "Austrian Footballer of the Year."
In January 2006, Ivanschitz transferred to Red Bull Salzburg and then to Greek Super League club Panathinaikos in August 2006 on a two-year loan. On 20 June 2008, Ivanschitz agreed on a permanent deal with Panathinaikos.
After three years in Greece with Panathinaikos he agreed on 18 July 2009 on a two-year loan with 1. FSV Mainz 05 with the view to a two-year permanent contract in the summer of 2011. Mainz took advantage of this contract option prematurely, and signed Ivanschitz permanently in January 2011.
Ivanschitz made his debut for Austria in a February 2003 friendly match against Greece, coming on as a substitute for Markus Weissenberger. He was also a participant at the UEFA Euro 2008. He has earned 50 caps for Austria and has scored eight goals.
He captained Austria for the first time when he was only 19 years old. Ivanschitz wears shirt number 10 in the national team and his position is in the midfield, preferably in an attacking position. Ivanschitz is considered the David Beckham of Austria, despite favouring his left foot; still the name stuck because of his exposure to the local media and popularity with the fans. In September 2009 he was abandoned by Austria's coach, Dietmar Constantini, who has said he will never call up the playmaker. He was called up again to the national team after Constantini stepped down as coach on 13 September 2011.