In 2006, she was already selected in the wider 24-man squad for the European Championship by head coach Armin Emrich, but she was eventually left out from the travelling squad. Müller finally made her full international debut on 18 October 2007 against Japan. She made it to the German team for the 2007 World Championship; she played six matches at the tournament, scoring two goals and winning the bronze medal. A year later, Müller decided not to participate at the 2008 European Championship, claiming she needs a break after a long and exhausting three-years period behind her.