The group, which includes the world's biggest container shipping company Maersk Line, posted a net profit of 13.4 billion Danish crowns ($2.3 billion) for the first six months of 2010, against a loss of 3.67 billion a year earlier.
The result for Denmark's biggest company beat all forecasts in a Reuters poll of analysts, where the average expectation was for a net profit of 9.12 billion crowns.
"Overall expectations for the A.P. Moller-Maersk Group are that the result for 2010 will exceed $4 billion," the group said in a statement on Wednesday, upgrading its outlook from last month that the result would exceed the 2008 level of $3.5 billion.
Shares in A.P. Moller-Maersk closed at 49,000 crowns on Monday, valuing the group at about $36.7 billion. Trade on the Copenhagen bourse resumes at 0700 GMT.