At age 17, Melis made her debut for the Dutch national team in 2004. Her goalscoring helped the Dutch qualify for their first major tournament, the UEFA Women's Euro 2009, where they reached the semi-finals. In the tournament, she scored a crucial goal in the final group game against Denmark to send her team into the knockout stage, and later converted a penalty in the shoot-out against France to help them win their quarter-final. At the Euro 2013 in Sweden and the 2015 FIFA Women's World Cup in Canada she played all seven combined matches for her country but did not score. When she retired from playing international football in 2016, she had earned 136 caps and scored 59 goals.