The Stuttgart Open (currently sponsored by Mercedes Benz and called the MercedesCup) is an ATP Tour 250 series tennis tournament on the ATP Tour. Between 1970 and 1989, the Stuttgart Open was a Grand Prix tennis circuit event. From 1990 to 1999, the Stuttgart Open was an ATP Championship Series tournament. The Championship Series name was changed to ATP International Series Gold in 2000, and the Stuttgart Open was a part of this series from 2000–2001 and 2003–2008. In 2002, the Stuttgart Open was briefly demoted for one year to ATP International Series status. In 2009, the series was renamed to the ATP Tour 250 series status, which the Stuttgart Open has retained ever since.
Held since 1916 in Stuttgart, Germany, the Stuttgart Open was played on clay up to and including 2014. Starting in 2015, the tournament is played on grass. Along with the move to grass courts, the tournament is now staged in the week after the French Open finishes.
Thomas Muster of Austria won the title twice in consecutive years (1995 and 1996).