Rasmussen made his debut for the senior Danish national team on 11 October 2008, as he played the last 13 minutes of the 3–0 win against Malta in the 2010 World Cup qualification. In January 2009, he was a part of the unofficial Denmark League XI national football team which won the 2009 King's Cup invitational tournament, under the management of Danish national coach Morten Olsen.
Rasmussen entered the senior Danish national team on October 11, 2008, in a decisive 3–0 victory over Malta during World Cup qualifying. He also participated in an unofficial all-star Denmark League XI team that won the King's Cup tournament in January 2009 under coach Morten Olsen.