He became the 12th migrant killed trying to cross the Channel to Britain this year.
"At around 8am, the driver of a heavy-goods vehicle checked his load, and found a deceased migrant in his lorry undoubtedly crushed by the pallets," the wooden platforms used to stack goods, said a source in the local prefecture.
Two family members were also found "safe and sound", the source added.
An investigation was opened by police.
Between 3,000 and 3,500 people, mostly from Africa and the Middle East, are gathered around the port, hoping to reach Britain, with several hundred more living in a camp around 40 kilometres (25 miles) from Calais.