Football's world governing body Fifa said using the image in his design would breach 'intellectual property rights' if used by Mercedes driver Rosberg at the German Grand Prix.
German Rosberg, 29, who leads his Mercedes team-mate Lewis Hamilton by four points in the title race, had hoped to wear the revised helmet design at Hockenheim this weekend.
But in a statement, Fifa said it was "obliged to take action against any unauthorized reproduction of its intellectual property in a commercial context."
It added: "We cannot allow a commercially branded helmet to feature the trophy as this would jeopardize the rights of our commercial affiliates.
"We appreciate Nico Rosberg's desire to congratulate the German team and have therefore been in discussions with the Rosberg team to attempt to find a solution whereby he is still able to show his support for Germany without using Fifa intellectual property in a commercial context."
Rosberg published a photograph of his helmet using his Twitter account.
"I would have loved to carry the trophy as a tribute to the guys," he said. "But I respect the legal situation."
He plans to retain other images on his helmet including his flag and four stars to represent four World Cup wins.
Rosberg is a keen soccer player and supporter and earlier this year enjoyed training briefly with Melbourne Victory ahead of racing in the Australian Grand Prix.