The Everton centre-back is confident of a Dutch victory but insists their first opponents of Euro 2012 could cause an upset
Bert van Marwijk's men are heavy favourites to get off to a winning start at Euro 2012 when they line-up against the Danes on Saturday night.
And, although Heitinga is confident that his side will collect the three points, he insists that Oranje must be careful not to fall victim to complacency.
"Denmark could surprise us," the 28-year-old told NUSport. "Although their expectations are a lot lower in this difficult group.
"Nobody really expects them to proceed. We owe it to our fans to beat Denmark."
The Everton centre-back expects Nicklas Bendtner to start up front for the Euro 1992 winners and is confident that he can handle the 24-year-old, whom he has come up against before in the Premier League.
"They are likely to play with Bendtner in the first-team," he added. "I've played against him many times and it has always gone well.
"I have won all the battles and have never conceded against him. The statistics look good, but this is a totally different game."
The Netherlands meet Denmark on Saturday at 20.45 CET.